Abstract:
Disclosed is a method for manufacturing a conductive film in which a mesh pattern comprising a wire material is provided on a base material. Also disclosed are a conductive film and a recording medium. Image data representing a mesh pattern is created on the basis of a plurality of selected positions. On the basis of said image data, an evaluation value which quantifies noise characteristics of the mesh pattern is computed. On the basis of the computed evaluation value and prescribed evaluation conditions, one image datum is chosen as an output image datum.

Description:
CROSS REFERENCE 
     This application is a Divisional of copending application Ser. No. 13/638,541, filed on Sep. 28, 2012, which was filed as PCT International Application No. PCT/JP2011/057582 on Mar. 28, 2011, which claims the benefit under 35 U.S.C. §119(a) to Patent Application No. JP2010-084645 and JP2010-084647, each filed in Japan on Mar. 31, 2010, all of which are hereby expressly incorporated by reference into the present application. 
    
    
     TECHNICAL FIELD 
     The present invention relates to a method (conductive film manufacturing method) for manufacturing a conductive film, in which a mesh pattern made up from wires is disposed on a substrate, as well as the conductive film itself, and a recording medium. 
     BACKGROUND ART 
     Recently, a conductive film has been developed in which a mesh pattern made up wires is disposed on a transparent substrate. The conductive film can be used as an electrode or a heat-generating sheet. Not only can such a conductive film be used as an electrode for a touch panel, or an electrode for an inorganic EL element, and organic EL element or a solar cell, but the conductive film may also be applied to a portion of a defroster (defrosting device), a window glass of a vehicle, etc., for example. 
     Depending on the use of the aforementioned various products, cases are known to occur in which such a mesh pattern produces considerable granular noise, which obstructs the visibility of objects to be observed. Various techniques have been proposed in which, by arranging the same or different mesh patterns in a regular or irregular manner, such granular noise is suppressed, whereby the visibility of objects to be observed can be improved. 
     For example, in Japanese Laid-Open Patent Publication 2009-094467, an image display device is disclosed having an electromagnetic shielding film and a moire (moiré) preventing film attached thereto, wherein the electromagnetic shielding film has a conductive portion and an opening portion, and the moire preventing film has a moire preventing part (see paragraph [0063], and FIGS. 1, 10A and 10B of the patent publication). As a result of this structure, localized increases of an integrated amount of transmitted light are suppressed, and a nearly constant integrated amount can be realized over the entirety of the film. In other words, by combining the conductive portion and the opening portion, potential formation of mesh patterns is eliminated, making it difficult for moire patterns to occur. 
     Further, in Japanese Laid-Open Patent Publication 2009-117683, a device and a method are disclosed in which two-dimensional power spectra are calculated respectively in relation to image data representing a pixel array pattern and an electromagnetic wave shielding pattern, and the shape of the electromagnetic wave shielding pattern is determined such that the difference in spatial frequency corresponding to peaks thereof exceeds a predetermined value (see paragraphs [0014] and [0024] of the patent publication). Consequently, generation of moire patterns can be suppressed, whereby an increase in surface resistivity and degradation in transparency can be avoided. 
     Furthermore, as shown in  FIG. 33A , according to Japanese Laid-Open Patent Publication No. 2009-137455, a window for a riding movable body and the shape of a pattern PT 1  thereof in plan view are disclosed, having a mesh layer  4 , in which rounded arcuate conductive wires  2  from which portions have been cutout are arranged repeatedly in a lattice shape, and respective ends of the arcuate wires  2  are connected to the vicinity of a center portion of another adjacent arcuate wire  2  (see paragraph [0029] and FIG. 3 of the patent publication). In accordance therewith, it is noted that not only visibility but also shielding of electromagnetic waves as well as resistance to breakage can be improved. 
     Further, as shown in  FIG. 33B , according to Japanese Laid-Open Patent Publication No. 2009-016700, a transparent conductive substrate and the shape of a pattern PT 2  thereof as viewed in plan are disclosed, which is manufactured using a solution, i.e., a self-organized metal particle solution, which forms a mesh-like structure naturally on the substrate if one side of the substrate is coated and then left untreated (see paragraphs [0022] to [0024] and FIG. 1 of the patent publication). In accordance therewith, it is noted that an irregular mesh-like structure can be obtained in which moire phenomena do not occur. 
     Moreover, as shown in  FIG. 33C , according to Japanese Laid-Open Patent Publication No. 2009-302439, a light transmissive electromagnetic shield material and the shape of a pattern PT 3  thereof as viewed in plan are disclosed, in which an electromagnetic shield layer  6  has a sea region structure in a sea-island configuration, wherein the shapes of island regions  8  made up from openings surrounded by the electromagnetic shield layer  6  differ mutually from each other (see paragraphs [0011] to [0015] and FIG. 1(B) of the patent publication). In accordance therewith, it is noted that both optical transparency and electromagnetic shielding are improved without the occurrence of moire patterns. 
     SUMMARY OF INVENTION 
     However, with the patterns PT 1 , PT 2  disclosed in Japanese Laid-Open Patent Publication No. 2009-137455 and Japanese Laid-Open Patent Publication No. 2009-16700, there are problems with such pattern configurations in relation to further reducing granular noise and improving visibility. 
     For example, in the mesh pattern PT 1  of Japanese Laid-Open Patent Publication No. 2009-137455, since the arcuate wires  2  are repeatedly arranged in a lattice shape, the periodicity of the wires  2  is extremely high. More specifically, if the power spectrum of the pattern PT 1  is calculated, it is predicted that the spatial frequency band corresponding to an inverse of the interval at which the wires  2  are arranged has a sharp peak. In this case, for improving visibility of the pattern PT 1 , the size (diameter) of the arcs must be made small. 
     Further, with the mesh shaped pattern PT 2  of Japanese Laid-Open Patent Publication No. 2009-016700, since the shape and size of the mesh is uneven, the irregularity thereof is extremely high. More specifically, if the power spectrum of the pattern PT 2  is calculated, the power spectrum is predicted to be of a substantially constant value irrespective of the spatial frequency band (close to the characteristics of white noise). For further improving visibility of the pattern PT 2 , the self-organizational size thereof must be made small. 
     If this is done, however, in either the window for a riding movable body of Japanese Laid-Open Patent Publication No. 2009-137455 or the transparent conductive substrate of Japanese Laid-Open Patent Publication No. 2009-016700, an inconvenience results in that optical transmittance and productivity are reduced for the purpose of improving visibility. 
     Furthermore, since the pattern PT 3  disclosed in Japanese Laid-Open Patent Publication No. 2009-302439 is not configured in a mesh shape, a variance occurs in the wiring shape of the cutting plane. In the case that the pattern PT 3  is used as an electrode, for example, an inconvenience results in that a stable power capability cannot be obtained. 
     The present invention has been made in order to address and solve the aforementioned problems, and has the object of providing a conductive film and a manufacturing method for a conductive film having a stable power capability even after being cut, which is capable of decreasing granular noise caused by the pattern, while also significantly improving the visibility of objects to be observed. Further, the present invention has the object of providing a recording medium storing a program for enabling a computer to create output image data used in manufacturing such a conductive film. 
     According to the present invention, a method for manufacturing a conductive film comprises a position selecting step for selecting plural positions from among a predetermined two-dimensional image region, an image data generating step for generating image data representing the pattern of a mesh pattern based on the selected plural positions, an evaluation value calculating step for calculating an evaluation value obtained by quantifying noise characteristics of the mesh pattern based on the generated image data, an image data determining step for determining as output image data one of the image data based on the calculated evaluation value and predetermined evaluation conditions, and a forming step of outputting and forming a wire material on a substrate material based on the determined output image data to thereby manufacture the conductive film having the mesh pattern. 
     In the foregoing manner, since the evaluation value calculating step for calculating an evaluation value obtained by quantifying noise characteristics of the mesh pattern based on the generated image data, and the image data determining step for determining as output image data one of the image data based on the calculated evaluation value and predetermined evaluation conditions are provided, the form of a mesh pattern having noise characteristics that satisfy the predetermined evaluation conditions can be determined. Stated otherwise, by suitably controlling the noise characteristics of the mesh pattern, the sensation of noise can be reduced. 
     Further, the method for manufacturing a conductive film may further comprise a structural pattern input step of inputting visual information of the pattern material in relation to visibility of the structural pattern in the case that a pattern material for forming a structural pattern having a pattern different from the pattern of the mesh pattern is superimposed on the conductive film and visual confirmation thereof is performed, and an image information estimating step of estimating image information of the structural pattern based on the input visual information of the pattern material, wherein based on the estimated structural pattern image information, the image data generating step may generate the image data representing a pattern in which the structural pattern is superimposed on the mesh pattern. Owing thereto, while considering an actual mode of use including the structural pattern, noise characteristics can be optimized. In particular, moire patterns generated by the mesh pattern and the structural pattern can be suppressed. 
     Furthermore, in the visual information, there may be included at least one of a type, a color value, an optical transmittance, and an optical reflectance of the pattern material, and an arrangement position, a unit shape, and a unit size of the structural pattern is included in the visual information of the pattern material. 
     Further, the pattern material may comprise a black matrix. 
     Preferably, the method for manufacturing a conductive film further comprises a first input step of inputting visual information of the wire material in relation to the visibility of the mesh pattern, a second input step of inputting visual information of the substrate material in relation to the visibility of the mesh pattern, and an estimating step of estimating image information of the mesh pattern based on the input visual information of the wire material and the substrate material, wherein, in the image data generating step, the image data is generated based on the estimated image information of the mesh pattern. 
     Further, the evaluation value may be an evaluation value representative of a degree of granularity. 
     Further, preferably, the evaluation value is an RMS granularity. 
     Further, preferably, the evaluation value is an RMS granularity corrected by a human visual response characteristic function. 
     Further, preferably, the human visual response characteristic function is a Dooley-Shaw function. 
     Further, the corrected RMS granularity may be an RMS granularity calculated using new image data obtained by implementing a filtering process corresponding to the human visual response characteristic function with respect to the image data. 
     Furthermore, in the image data generating step, a mesh-shaped pattern may be formed from the plural positions using a Delaunay triangulation method, whereby image data representing the pattern is created. 
     Furthermore, in the image data generating step, a mesh-shaped pattern may be formed from the plural positions using a Voronoi diagram, whereby image data representing the pattern is created. 
     Further, the method for manufacturing a conductive film preferably further comprises a position updating step of respectively updating part of the plural positions with other positions based on the evaluation value, wherein the position updating step, the image data generating step, and the evaluation value calculating step are repeated successively, and the output image data is determined by the image data determining step. 
     In the position updating step, preferably, the part of the plural positions are updated with the other positions respectively using a simulated annealing method. 
     A conductive film according to the present invention is manufactured utilizing any of the aforementioned manufacturing methods. 
     A conductive film according to the present invention includes a mesh pattern comprising a plurality of polygonal meshes, wherein the mesh pattern is formed such that, in relation to a power spectrum of a centroid position distribution of the meshes, an average intensity in a spatial frequency band higher than a predetermined spatial frequency is greater than an average intensity in a spatial frequency band lower than the predetermined spatial frequency. 
     Further, the predetermined spatial frequency preferably is a spatial frequency at which a human visual response characteristic corresponds to 5% of a maximum response thereof. 
     Furthermore, the human visual response characteristic may be a visual response characteristic obtained based on a Dooley-Shaw function at a visibility distance of 300 mm, wherein the predetermined spatial frequency is 6 cycle/mm. 
     According to the present invention, there is provided a recording medium storing a program for enabling a computer to create output image data for use in manufacturing a conductive film, wherein the program further enables the computer to function as a position selecting unit for selecting plural positions from among a predetermined two-dimensional image region, an image data generating unit for generating image data representing the pattern of a mesh pattern based on the plural positions selected by the position selecting unit, an evaluation value calculating unit for calculating an evaluation value obtained by quantifying noise characteristics of the mesh pattern based on the image data generated by the image data generating unit, and an image data determining unit for determining as output image data one of the image data based on the evaluation value calculated by the evaluation value calculating unit and predetermined evaluation conditions. 
     According to the conductive film manufacturing method, the conductive film, and the storage medium of the present invention, image data representative of the pattern of a mesh pattern is generated based on the plural selected positions, an evaluation value is calculated by quantifying noise characteristics of the mesh pattern based on the generated image data, and one of the plural image data is determined as output image data based on the calculated evaluation value and predetermined evaluation conditions. Therefore, the form of a mesh pattern having noise characteristics that satisfy the predetermined evaluation condition can be determined. Stated otherwise, by optimally controlling the noise characteristics of the mesh pattern, the sensation of noise can be reduced. 
     According to the conductive film of the present invention, in relation to a power spectrum of a centroid position distribution of respective meshes, a mesh pattern is formed such that an average intensity in a spatial frequency band higher than a predetermined spatial frequency is greater than an average intensity in a spatial frequency band lower than the predetermined spatial frequency. Therefore, compared to a low spatial frequency band, the noise level on the side of the high spatial frequency band is relatively large. Although human visual perception has a high response characteristic in a low spatial frequency band, in mid to high spatial frequency bands, properties of the response characteristic decrease rapidly, and thus, the sensation of noise as perceived visually by humans tends to decrease. In accordance with this phenomenon, the sensation of granular noise caused by the pattern of the transparent conductive film is capable of being lowered, and the visibility of objects to be observed can be significantly enhanced. Further, because a plurality of polygonal meshes are provided, the cross sectional shape of the respective wires after cutting is substantially constant, and thus the conductive film exhibits a stable conducting capability. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is an outline schematic block diagram of a manufacturing apparatus for manufacturing a conductive film according to an embodiment of the present invention; 
         FIG. 2A  is a partially enlarged plan view of the conductive film of  FIG. 1 ; 
         FIG. 2B  is an outline exploded perspective view showing a structural example of a case in which the conductive film of  FIG. 1  is applied to a touch panel; 
         FIG. 3  is an outline cross sectional view of the conductive film of  FIG. 2A ; 
         FIG. 4  is a functional block diagram of a mesh pattern evaluating unit and a data update instructing unit shown in  FIG. 1 ; 
         FIG. 5  is a view showing a first setting screen for setting image data creating conditions; 
         FIG. 6  is a view showing a second setting screen for setting image data creating conditions; 
         FIG. 7  is a flowchart providing a description of operations of the manufacturing apparatus of  FIG. 1 ; 
         FIG. 8A  is an outline schematic diagram in which image data representative of a mesh pattern are made visual; 
         FIG. 8B  is a diagram of a two-dimensional power spectrum obtained by implementing a fast Fourier transform on the image data of  FIG. 8A ; 
         FIG. 8C  is a cross sectional view taken along line VIIIC-VIIIC of the two-dimensional power spectrum shown in  FIG. 8B ; 
         FIG. 9  is a graph of a Dooley-Shaw function (observational distance of 300 mm); 
         FIG. 10  is a first flowchart explaining a method of creating output image data; 
         FIG. 11  is a graph showing an example of a relationship between a seed point arrangement density and total transmittance; 
         FIGS. 12A and 12B  are explanatory diagrams of results using a Voronoi diagram, in which eight regions surrounding eight points are defined; 
         FIGS. 13A and 13B  are explanatory diagrams of results using a Delaunay triangulation method, in which eight triangular regions are defined by respective vertices of eight points; 
         FIG. 14A  is an explanatory diagram showing pixel address definitions in image data; 
         FIG. 14B  is an explanatory diagram showing pixel value definitions in image data; 
         FIG. 15A  is a schematic diagram of initial positions of seed points; 
         FIG. 15B  is a Voronoi diagram formed on the basis of the seed points of  FIG. 15A ; 
         FIG. 16  is a detailed flowchart of step S 26  shown in  FIG. 10 ; 
         FIG. 17A  is an explanatory drawing showing a positional relationship between first seed points, second seed points, and candidate points within an image region; 
         FIG. 17B  is an explanatory drawing of a result in which the second seed points and the candidate points are exchanged to update the seed point positions; 
         FIG. 18  is a cross sectional view taken along the X-axis of two-dimensional power spectra obtained by effecting FFT respectively on image data of various patterns according to comparative examples and of a mesh pattern according to a present embodiment; 
         FIG. 19  is an explanatory drawing showing centroid positions of each of the regions shown in  FIG. 12B ; 
         FIG. 20  is an outline explanatory drawing showing a relationship between plural meshes and centroid positions of the meshes, in relation to a first mesh pattern according to the present embodiment; 
         FIG. 21A  is an outline explanatory drawing in which image data is made visible showing a distribution of centroid positions of respective meshes having the mesh pattern of  FIG. 20 ; 
         FIG. 21B  is a distribution diagram of a two-dimensional power spectrum obtained by effecting FFT with respect to the image data of  FIG. 21A ; 
         FIG. 21C  is a cross sectional view taken along line XXIC-XXIC of the distribution of the two-dimensional power spectrum shown in  FIG. 21B ; 
         FIG. 22  is a comparative drawing illustrating the spectra shown in  FIG. 8C  and the centroid spectrum shown in  FIG. 21C ; 
         FIG. 23  is an outline explanatory drawing representative of characteristics of the power spectrum of  FIG. 21C ; 
         FIG. 24  is a second flowchart explaining the method of creating output image data; 
         FIG. 25  is a detailed flowchart of step S 26 A shown in  FIG. 24 ; 
         FIG. 26A  is a visual outline explanatory drawing in which a black matrix is superimposed on output image data representing the pattern of a conductive film; 
         FIGS. 26B through 26D  are graphs representing results in which R-component, G-component, and B-component color values within the image data of  FIG. 26A  are extracted respectively and power spectra are calculated therefrom; 
         FIG. 27A  is a visual outline explanatory drawing in which human visual response characteristics are applied with respect to the image data of  FIG. 26A ; 
         FIGS. 27B through 27D  are graphs representing results in which R-component, G-component, and B-component color values within the image data of  FIG. 27A  are extracted respectively and power spectra are calculated therefrom; 
         FIG. 28A  is an outline explanatory view of visual image data representative of a first mesh pattern optimized under conditions of not being superimposed with a black matrix; 
         FIG. 28B  is an outline explanatory view of visual image data representative of a second mesh pattern optimized under conditions of being superimposed with a black matrix; 
         FIGS. 29A through 29E  are process diagrams showing a first conductive film manufacturing method according to the present embodiment; 
         FIGS. 30A and 30B  are process diagrams showing a second conductive film manufacturing method according to the present embodiment; 
         FIGS. 31A and 31B  are process diagrams showing a third conductive film manufacturing method according to the present embodiment; 
         FIG. 32  is a process diagram showing a fourth conductive film manufacturing method according to the present embodiment; and 
         FIGS. 33A through 33C  are enlarged plan views of patterns in accordance with respective comparative examples. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Below, with reference to the accompanying drawings, an explanation shall be given of a preferred embodiment in relation to a manufacturing apparatus for carrying out a conductive film manufacturing method according to an embodiment of the present invention. 
       FIG. 1  is an outline schematic block diagram of a manufacturing apparatus  10  for manufacturing a conductive film  14  according to the present embodiment. 
     The manufacturing apparatus  10  basically comprises an image processing device  12  for creating image data Img (including output image data ImgOut) representative of a pattern corresponding to a mesh pattern M, an exposure unit  18  for performing exposure by illuminating the conductive film  14  with light  16  under a manufacturing process based on the output image data ImgOut created by the image processing device  12 , an input device  20  for inputting to the image processing device  12  each of various conditions (including visual information of a mesh pattern M and a later-described structural pattern) for creating the image data Img, and a display device  22  for displaying a GUI image to assist in an input operation by the input device  20 , and for displaying stored output image data ImgOut or the like. 
     The image processing device  12  comprises a storage unit  24  storing therein image data Img, output image data ImgOut, position data SPd of candidate points SP, and position data SDd of seed points SD, a random number generator  26  for producing a pseudo-random number and generating a random number value, an initial position selecting unit  28  (position selecting unit) for selecting initial positions of seed points SD from among a predetermined two-dimensional image using the random number value generated by the random number generator  26 , an updated candidate position determining unit  30  (position selecting unit) for determining positions (excluding positions of the seed points SD) of candidate points SP from among the two-dimensional image region using the random number value, an exposure data conversion unit  32  for converting output image data ImgOut into a control signal (exposure data) of the exposure unit  18 , and a display controller  34  for controlling display of respective images on the display device  22 . 
     The seed points SD are made up from first seed points SDN that are not to be updated, and second seed point SDS that are to be updated. Stated otherwise, the position data SDd of the seed points SD are constituted from position data SDNd of the first seed points SDN, and position data SDSd of the second seed points SDS. 
     A non-illustrated controller, which is constituted by a CPU or the like, is capable of implementing all of the controls in relation to image processing, by reading and executing a program stored in a recording medium (a non-illustrated ROM or the storage unit  24 ). 
     The image processing device  12  further comprises an image information estimating unit  36  for estimating image information of a mesh pattern M or a structural pattern based on visual information (described later) input from the input device  20 , an image data generating unit  38  for generating image data Img representative of a pattern corresponding to the mesh pattern M or the structural pattern based on image information supplied from the image information estimating unit  36  and positions of seed points SD supplied from the storage unit  24 , a mesh pattern evaluating unit  40  that calculates an evaluation value EVP for evaluating a mesh-shaped pattern based on the image data Img created by the image data generating unit  38 , and a data update instructing unit  42  for instructing updating/non-updating of data of seed points SD, evaluation values EVP, etc. based on the evaluation value EVP calculated by the mesh pattern evaluating unit  40 . 
     As shown in  FIG. 2A , the conductive film  14  of  FIG. 1  includes a plurality of conductive portions  50  and a plurality of openings  52 . The plural conductive portions  50  form a mesh pattern M (mesh-shaped wirings) in which a plurality of thin wires  54  mutually intersect. More specifically, a mesh shape is formed by a combination of one of the openings  52  and at least two conductive portions  50  that surround the one opening  52 . In the mesh shape, each of the openings  52  differs from the others, the openings  52  being arrayed irregularly (i.e., aperiodically) respectively. Below, at times, the material constituting the conductive portion  50  is referred to as a “wire material”. 
     The line width of the metallic thin wires  54  can be selected to be from 5 μm or greater to 200 μm (0.2 mm) or less. Of course, if it is desired to increase light-transmittance, the line width may be selected from between 5 μm or greater to 50 μm or less. Further, the area of the openings  52  preferably is from 0.02 mm 2  or greater to 40 mm 2  or less, and more preferably, is from 0.1 mm 2  or greater to 1 mm 2  or less. 
     Due to being constituted in the foregoing manner, a total optical transmittance of the conductive film  14  can be realized, which is from 70% or greater to less than 99%, from 80% or greater to less than 99%, and from 85% or greater to less than 99%. 
     The conductive film  14  is a conductive film that can be used as an electrode for a touch panel, or as an electrode for an inorganic EL element, an organic EL element or a solar cell. As shown in  FIG. 3 , the conductive film  14  comprises a transparent film substrate  56  (substrate), as well as the conductive portions  50  and the openings  52 , which are formed on the transparent film substrate  56 . 
     An outline exploded perspective view of a case in which the conductive film  14  is used as a touch panel electrode is shown in  FIG. 2B . A filter member  57  having the same size as the conductive film  14  is arranged by being superimposed on a surface of the conductive film  14 . The filter member  57  comprises a plurality of red filters  58   r , a plurality of green filters  58   g , and a plurality of blue filters  58   b , and a black matrix  59  (structural pattern). Below, the material constituting the black matrix  59  may also be referred to as a “pattern material”. 
     The red filters  58   r  (the green filters  58   g , or the blue filters  58   b ) are arranged respectively in parallel in a vertical (up/down) direction of the filter member  57 . Further, the red filters  58   r , the green filters  58   g , the blue filters  58   b , the red filters  58   r , . . . , are arranged in series periodically in a lateral (left/right) direction of the filter member  57 . More specifically, a planar region in which one red filter  58   r , one green filter  58   g , and one blue filter  58   b  are arranged is constituted as a unit pixel  60  capable of displaying any arbitrary color through a combination of red light emission, green light emission, and blue light emission. 
     The black matrix  59  has the function of a light shielding material for preventing mixing of reflective light from the exterior, or transmissive light from a non-illustrated back light at each of the adjacent unit pixels  60 . The black matrix  59  is made up from light shielding materials  61   h  extending in a horizontal direction, and light shielding materials  61   v  extending in a vertical direction. The light shielding materials  61   h ,  61   v  form a rectangular lattices, which each surrounds one set of color filters (i.e., the red filter  58   r , the green filter  58   g , and the blue filter  58   b ) that constitutes one unit pixel  60 . 
     Further, the conductive film  14  also functions as a transparent heating element for generating heat upon flow of a current therethrough. In this case, first and second electrodes are formed at opposing ends of the conductive film  14 , and a current flows from the first electrode to the second electrode. Consequently, the transparent heating element generates heat, whereby an object to be heated (e.g., a building glass window, an automotive glass window, a front cover for a vehicle lamp, etc.), which is placed in contact with or incorporating therein the transparent heating element, is heated. As a result, snow or the like adhering to the object to be heated can be removed. 
       FIG. 4  is a functional block diagram of the mesh pattern evaluating unit  40  and the data update instructing unit  42  shown in  FIG. 1 . 
     The mesh pattern evaluating unit  40  comprises an FFT operating unit  100 , which carries out fast Fourier transformation (hereinafter also referred to as FFT) on the image data supplied from the image data generating unit  38  to obtain two-dimensional spectral data (hereinafter referred to as a “spectrum Spc”), and an evaluation value calculating unit  102  for calculating an evaluation value EVP based on the spectra Spc supplied from the FFT operating unit  100 . 
     The data update instructing unit  42  comprises a counter  108  for counting the number of evaluations performed by the mesh pattern evaluating unit  40 , a simulated temperature management unit  110  for managing values of simulated temperatures T utilized by a later-described simulated annealing method, an update probability calculation unit  112  for calculating an update probability of the seed points SD based on the evaluation value EVP supplied from the mesh pattern evaluating unit  40  and a simulated temperature T supplied from the simulated temperature management unit  110 , a position update determining unit  114  for determining whether to update or not update position data SDd of seed points SD based on the update probability supplied from the update probability calculation unit  112 , and an output image data determining unit  116  for determining, as output image data ImgOut, one of the image data Img corresponding to a notification from the simulated temperature management unit  110 . 
       FIG. 5  is a view showing a first setting screen  120  for setting image data generating conditions. 
     The setting screen  120  comprises, from the top thereof and in the following order, a left side pull down menu  122 , a left side display column  124 , a right side pull down menu  126 , a right side display column  128 , seven text boxes  130 ,  132 ,  134 ,  136 ,  138 ,  140 ,  142 , and buttons  144 ,  146  labeled “CANCEL” and “NEXT” respectively. 
     To the left of the pull down menus  122  and  126 , text is displayed indicating “TYPE”. By operating the input device  20  (e.g., a mouse), non-illustrated selection columns are displayed below the pull down menus  122 ,  12 , to enable the items displayed therein to be selected. 
     The display column  124  is made up from five respective columns  148   a ,  148   b ,  148   c ,  148   d ,  148   e  with text labels “TRANSMITTANCE”, “REFLECTANCE”, “COLOR VALUE L*”, “COLOR VALUE a*” and “COLOR VALUE b*” displayed respectively to the left thereof. 
     Similar to the display column  124 , the display column  128  is made up from five respective columns  150   a ,  150   b ,  150   c ,  150   d ,  150   e  with text labels “REFLECTANCE”, “TRANSMITTANCE”, “COLOR VALUE L*”, “COLOR VALUE a*” and “COLOR VALUE b*” displayed respectively to the left thereof. 
     The label “TOTAL TRANSMITTANCE” is displayed to the left of the text box  130 , and “%” is displayed on the right hand side thereof. The label “FILM THICKNESS” is displayed to the left of the text box  132 , and “μm” is displayed on the right hand side thereof. The label “WIRING WIDTH” is displayed to the left of the text box  134 , and “μm” is displayed on the right hand side thereof. The label “WIRING THICKNESS” is displayed to the left of the text box  136 , and “μm” is displayed on the right hand side thereof. The label “PATTERN SIZE H” is displayed to the left of the text box  138 , and “mm” is displayed on the right hand side thereof. The label “PATTERN SIZE V” is displayed to the left of the text box  140 , and “mm” is displayed on the right hand side thereof. The label “IMAGE RESOLUTION” is displayed to the left of the text box  142 , and “dpi” is displayed on the right hand side thereof. 
     Further, by performing a predetermined operation using the input device  20  (e.g., keyboard), Arabic numerals can be input into any of the seven text boxes  130 ,  132 ,  134 ,  136 ,  138 ,  140 ,  142 . 
       FIG. 6  is a view showing a second setting screen for setting image data generating conditions. 
     The setting screen  160  has, from the top thereof and in the following order, two radio buttons  162   a ,  162   b , six text boxes  164 ,  166 ,  168 ,  170 ,  172 ,  174 , a matrix-shaped image  176 , and buttons  178 ,  180 ,  182  labeled respectively with “RETURN”, “SET”, and “CANCEL”. 
     The words “PRESENCE” and “ABSENCE” are displayed respectively to the right of the radio buttons  162   a  and  162   b . In addition, to the left of the radio button  162   a , the text label “PRESENCE/ABSENCE OF MATRIX” is displayed. 
     To the left of the text boxes  164 ,  166 ,  168 ,  170 ,  172 ,  174 , the text labels, “AVERAGE SAMPLE NUMBER OF SUPERIMPOSED POSITIONS”, “DENSITY”, “DIMENSIONS”, “a”, “b”, “c”, and “d” are displayed respectively. Further, to the right of the text boxes  164 ,  166 ,  168 ,  170 ,  172 ,  174 , the text labels “TIMES”, “D”, “μm”, “μm”, “μm”, and “μm” are displayed respectively. By performing a predetermined operation using the input device  20  (e.g., a keyboard), Arabic numerals can be entered in any of the text boxes  164 ,  166 ,  168 ,  170 ,  172 ,  174 . 
     The matrix-shaped image  176  is an image that simulates the form of the black matrix  59 , and is provided with four openings  184  and a window frame  186 . 
     Operations of the manufacturing apparatus  10  constructed basically as described above will be described below with reference to the flowchart of  FIG. 7 . 
     Initially, a method of creating a first mesh pattern M 1  suitable under conditions in which a black matrix  59  is not superimposed will be described. Thereafter, a method of creating a second mesh pattern M 2 , which is suitable under conditions in which a black matrix  59  is superimposed thereon, will be described while focusing on differences from the case of the mesh pattern M 1 . Hereinafter, for cases in which the first mesh pattern M 1  and the second mesh pattern M 2  need not be distinguished from each other, such cases will be indicated simply as “mesh patterns M”. 
     First, various conditions necessary for creating the image data Img representing the pattern corresponding to the mesh pattern M (including the output image data ImgOut) are input (step S 1 ). 
     The operator inputs appropriate numerical values, etc. via the setting screen  120  (see  FIG. 5 ) shown on the display device  22 . As a result, visual information can be input concerning visibility of the mesh pattern M. Visual information of the mesh pattern M is defined by various information that contribute to the shape and optical density of the mesh pattern M, including visual information of the wire material (metallic thin wire  54 ), and visual information of the transparent substrate (transparent film substrate  56 ). As visual information of the wire material, there may be included, for example, at least one of the type, color value, optical transmittance, and optical reflectance of the wire material, and the cross sectional shape and thickness of the metallic thin wire  54 . As visual information of the transparent substrate, there may be included, for example, at least one of the type, color value, optical transmittance, optical reflectance, and film thickness of the transparent substrate. 
     In relation to the conductive film  14  to be manufactured, the operator selects one of the types of wire materials using the pull down menu  122 . In the example of  FIG. 5 , “SILVER (Ag)” is selected. Upon selecting one type of wire material, the display column  124  is updated immediately, and predetermined numerical values are newly displayed corresponding to physical properties of the wire material. Values for optical reflectivity (units: %), optical reflectance (unit: %), color value L*, color value a*, color value b* (CIELAB) of silver having a thickness of 100 μm are displayed respectively in the columns  148   a ,  148   b ,  148   c ,  148   d , and  148   e.    
     Further, in relation to the conductive film  14  to be manufactured, the operator selects one of the types of film materials (transparent film substrate  56 ) using the pull down menu  126 . In the example of  FIG. 5 , “PET FILM” is selected. Upon selecting one type of film material, the display column  128  is updated immediately, and predetermined numerical values are newly displayed corresponding to physical properties of the film material. Values for optical reflectivity (units: %), optical reflectance (unit: %), color value L*, color value a*, color value b* (CIELAB) of a 1 mm thickness PET film are displayed respectively in the columns  150   a ,  150   b ,  150   c ,  150   d , and  150   e.    
     By selecting the item “MANUAL INPUT” (not shown) via the pull down menus  122 ,  126 , various physical property values can be input directly from the display columns  124 ,  128 . 
     Furthermore, in relation to the conductive film  14  to be manufactured, the operator enters various conditions of the mesh pattern M respectively using the text box  130 , etc. 
     The values input to the text boxes  130 ,  132 ,  134 ,  136  correspond respectively to total optical transmittance (units: %), film thickness of the transparent film substrate  56  (units: μm), line width of the metallic thin wires  54  (units: μm), and thickness of the metallic thin wires  54  (units: μm). 
     The values input to the text boxes  138 ,  140 ,  142  correspond respectively to the horizontal size of the mesh pattern M, the vertical size of the mesh pattern M, and the image resolution (pixel size) of the output image data ImgOut. 
     After having finished the input operations on the setting screen  120 , the operator clicks the “NEXT” button  146 , whereupon the display controller  34  changes the setting screen  120  shown on the display device  22  to the setting screen  160  shown in  FIG. 6 . 
     Through the setting screen  160  displayed on the display device  22 , the operator respectively inputs each of various conditions of the black matrix  59 . Inputs made via the radio buttons  162   a ,  162   b  correspond to whether or not the output image data ImgOut, which is representative of the superimposed pattern of the black matrix  59  on the mesh pattern M, is to be created. If “PRESENCE” (radio button  162   a ) is selected, the black matrix  59  is superimposed, and if “ABSENCE” (radio button  162   b ) is selected, the black matrix  59  is not superimposed. In the present case, since the black matrix  59  is not intended to be superimposed, the radio button  162   b  is selected. 
     Responsive to an operator clicking on the “SET” button  180 , the image information estimating unit  36  estimates the image information of the mesh pattern M. Such image information is referred to at the time that the image data Img (including the output image data ImgOut) is created. 
     For example, based on the vertical size of the mesh pattern M (the value input to the text box  138 ) and the image resolution of the output image data ImgOut (the value input to the text box  142 ), the number of pixels in the horizontal direction of the output image data can be calculated, and based on the width of the wiring (the value input to the text box  134 ) and the image resolution, the number of pixels corresponding to the line width of the metallic thin wires  54  can be calculated. 
     Further, based on the optical transmittance of the wire material (the value displayed in column  148   a ) and the thickness of the wires (the value input to the text box  136 ), the optical transmittance of the metallic thin wires  54  themselves can be estimated. In addition thereto, based on the optical transmittance of the film material (the value displayed in the column  150   a ) and the film thickness (the value input to the text box  132 ), the optical transmittance under a condition in which the metallic thin wires  54  are laminated on the transparent film substrate  56  can be estimated. 
     Furthermore, based on the optical transmittance of the wire material (the value displayed in the column  148   a ), the optical transmittance of the film material (the value displayed in the column  150   a ), the total transmittance (the value input to the text box  130 ), and the width of the wires (the value input to the text box  132 ), the number of openings  52  can be estimated together with estimating the number of seed points SD. The number of seed points SD may also be estimated responsive to an algorithm which determines regions of the openings  52 . 
     Next, output image data ImgOut is generated for creating the mesh pattern M (step S 2 ). 
     Prior to describing the method of creating output image data ImgOut, a method of evaluating the image data Img will first be described. In the present embodiment, an evaluation is performed based on an evaluation value EVP obtained by quantifying noise characteristics (e.g., granular noise). 
     As one example of evaluating noise characteristics, the range of a predetermined region of the image data Img may be determined, and then the RMS (Root Mean Square) may be determined with respect to pixel values within the range of the region. The present embodiment uses an evaluation value EVP that is improved by adopting evaluation of human visual response characteristics. 
       FIG. 8A  is an outline schematic diagram in which image data Img representing the pattern of the mesh pattern M are made visual. Below, the image data Img shall be explained by way of example. 
     First, FFT is effected on the image data Img shown in  FIG. 8A . As a result, concerning the shape of the mesh pattern M, the overall tendency (spatial frequency distribution) thereof can be grasped, rather than a partial shape. 
       FIG. 8B  is a diagram of a spectrum Spc obtained by implementing FFT on the image data Img of  FIG. 8A . The horizontal axis of the spectrum diagram indicates the spatial frequency in the X-axis direction, whereas the vertical axis indicates the spatial frequency in the Y-axis direction. Further, as the displayed density within each spatial frequency band becomes thinner, the intensity level (spectral value) becomes smaller, and as the displayed density becomes denser, the intensity level becomes greater. In the example shown in the diagram, the spectral distribution of the spectrum Spc is isotropic having two annular peaks. 
       FIG. 8C  is a cross sectional view taken along line VIIIC-VIIIC of the spectrum Spc shown in  FIG. 8B . Because the spectrum Spc is isotropic, the cross section thereof corresponds to a radial distribution with respect to all angular directions. As understood from the present drawing, the intensity level becomes small in a low spatial frequency band and in a high spatial frequency band, whereas the intensity level is high only in an intermediate spatial frequency band, thereby exhibiting a so-called band-pass characteristic. More specifically, according to common technical terminology in the field of image engineering, the image data Img shown in  FIG. 8A  is representative of a pattern having a “green noise” characteristic. 
       FIG. 9  is a graph of a Dooley-Shaw function viewed at an observational distance of 300 mm. 
     A Dooley-Shaw function is one type of VTF (Visual Transfer Function), which is a representative function that simulates human visual response characteristics. More specifically, the function corresponds to the square of a luminance contrast ratio characteristic. The horizontal axis on the graph is the spatial frequency (units: cycle/mm), whereas the vertical axis is the value of the VTF (units of which are non-dimensional). 
     If the observational distance is set at 300 mm, values of the VTF are constant (equivalent to 1) within a range of 0 to 1.0 cycle/mm, and as the spatial frequency grows higher, there is a tendency for the VTF values to decrease. More specifically, the function operates as a low pass filter that blocks or cuts off mid to high spatial frequency bands. 
     Actual human visual response characteristics exhibit the characteristics of a so-called bandpass filter, in which the value thereof becomes smaller than 1 in the vicinity of 0 cycle/mm. However, as exemplified in  FIG. 9 , in the present embodiment, by setting the VTF value to 1 even in extremely low spatial frequency bands, the contribution to the evaluation value EVP is high. Consequently, an effect is obtained of suppressing periodicity due to repeated arrangement of the mesh pattern M. 
     In a case where the value of the spectrum Spc is defined by F(Ux, Uy), the evaluation value EVP is calculated by the following Formula (1). 
     
       
         
           
             
               
                 
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     According to the Wiener-Khintchen theorem, the value obtained by integrating the spectrum Spc over the total spatial frequency band matches the square of the RMS. A value obtained by multiplying the VTF with respect to the spectrum Spc, and then integrating the new spectrum Spc over the total spatial frequency band yields an evaluation index that substantially matches human visual characteristics. The evaluation value EVP can be provided by the RMS corrected by the human visual response characteristics. Similar to an ordinary RMS, the evaluation value EVP typically is taken to be a value that is equal to or greater than zero, and the closer the evaluation value EVP is to zero, the better the noise characteristics are. 
     Further, by effecting an inverse Fourier transform (e.g., IFFT) with respect to the VTF shown in  FIG. 9 , a mask corresponding to the VTF is calculated in real space, and by applying the mask with respect to image data Img to be evaluated and performing a convolution operation thereon, the RMS may be determined with respect to the new image data Img. Consequently, an operational result can be obtained, which is equivalent to that obtained by the above-described method using formula (1). 
     It goes without saying the formula for computing the evaluation value EVP may be modified in various ways, responsive to the evaluation function and the target level (acceptable range or tolerance) for determining the mesh pattern M. 
     Below, a detailed method for determining output image data ImgOut based on the aforementioned evaluation value EVP shall be explained. For example, a method can be used in which generation of image data Img for different patterns, and evaluation thereof by the evaluation value EVP are repeatedly successively. 
     Included in the image data Img are image data ImgInit, which serve as initial data in the repeated calculations, as well as image data ImgTemp, which serve as temporary data. Further, included in the evaluation value EVP is an evaluation value EVPInit, which serves as an initial value in the repeated calculations, as well as an evaluation value EVPTemp, which serves as temporary data. 
     In this case, as an optimization problem for determining the output image data ImgOut, various search algorithms can be used, such as a constructive algorithm or an iterative improvement algorithm, etc. 
     Primarily with reference to the flowchart of  FIG. 10  and the functional block diagram of  FIG. 1 , explanations shall be given concerning an optimization method for optimizing the mesh pattern M by means of a simulated annealing method (hereinafter referred to as an SA method) according to the present embodiment. The SA method is a stochastic search algorithm modeled on an “annealing method” for obtaining robust iron by striking iron in a high temperature condition. 
     First, the initial position selecting unit  28  selects initial positions of seed points SD (step S 21 ). 
     Prior to selecting the initial positions, the random number generator  26  generates a random number value using a pseudo-random number generating algorithm. As one such pseudo-random number generating algorithm, any of various algorithms may be used, such as a Mersenne Twister, an SIMD-Oriented Fast Mersenne Twister (SFMT), or an Xorshift method. Then, using the random number value supplied from the random number generator  26 , the initial position selecting unit  28  determines initial positions of the seed points SD in a random fashion. Herein, the initial position selecting unit  28  selects initial positions of the seed points SD as pixel addresses in the image data Img, and the seed points SD are set at respective positions that do not overlap one another. 
     Based on the number of pixels in vertical and horizontal directions of the image data Img supplied from the image information estimating unit  36 , the initial position selecting unit  28  determines beforehand the range of the two-dimensional image region. Further, the initial position selecting unit  28  acquires beforehand from the image information estimating unit  36  the number of seed points SD, and based thereon, the number of seed points SD is determined. 
       FIG. 11  is a graph showing an example of a relationship between an arrangement density of seed points SD and the total transmittance of the mesh pattern M. In the illustrated graph, it is shown that as the arrangement density becomes higher, the coverage area of the wires increases, and as a result, the total transmittance of the mesh pattern decreases. 
     The graph characteristics exhibit changes responsive to the optical transmittance of the film material (as indicated in the column  150   a  of  FIG. 5 ), the wiring width (the value input to the text box  132  of  FIG. 5 ), and a region determining algorithm (e.g., a Voronoi diagram). Thus, characteristic data responsive to each of the parameters such as wiring width or the like may be stored beforehand in the storage unit  24 , in any of various data formats consisting of functions, tables, or the like. 
     Further, a correspondence between the arrangement density of the seed points SD and an electrical resistance value of the mesh pattern M may be acquired beforehand, whereby the number of seed points SD may be determined based on a specified electrical resistance value. The electrical resistance value is one parameter indicative of electrical conductivity of the conductive portion  50 , which is essential to the design of the mesh pattern M. 
     The initial position selecting unit  28  may also select the initial positions of the seed points SD without using a random number value. For example, the initial positions can be determined by referring to data acquired from an external apparatus including a non-illustrated scanner or storage device. Such data, for example, may be predetermined binary data, and more specifically, may be halftone data used for printing. 
     Next, the image data generating unit  38  generates image data ImgInit that serves as initial data (step S 22 ). The image data generating unit  38  generates image data ImgInit representing the pattern corresponding to the mesh pattern M, based on the number of seed points SD and the position data SDd supplied from the storage unit  24 , along with image information supplied from the image information estimating unit  36 . 
     A variety of methods may be adopted as the algorithm for determining a mesh-shaped pattern from multiple seed points SD. Below, explanations shall be given in detail with reference to  FIGS. 12A through 13B . 
     As shown in  FIG. 12A , for example, it is assumed that eight points P 1  to P 8  are selected at random from within a rectangular two-dimensional image region  200 . 
       FIG. 12B  is an explanatory diagram of results using a Voronoi diagram, in which eight regions V 1  through V 8  surrounding eight points P 1  to P 8  respectively are defined. Euclidean distance is used as a distance function. As can be understood from the drawing, with respect to the arbitrary points from within the region V i  (where i=1 to 8), the point P i  is shown to be the closest point of the points P. 
     Further, in  FIG. 13B , a result is shown in which eight triangular regions are defined by respective vertices of the points P 1  to P 8  of  FIG. 13A  (which is the same as  FIG. 12A ) using a Delaunay triangulation method. 
     Delaunay triangulation is a method of defining triangular shapes by connecting adjacent points from among the points P 1  to P 8 . According to this method as well, regions V 1  to V 8  can be determined in the same number as the number of points P 1  to P 8 . 
     Incidentally, prior to generating the image data Img (including the image data ImgInit and ImgTemp as well as the output image data ImgOut), definitions of pixel addresses and pixel values therefor are determined beforehand. 
       FIG. 14A  is an explanatory diagram showing image pixel address definitions in the image data Img. For example, it is assumed that the pixel size is 10 μm, and the number of pixels in both vertical and horizontal directions of the image data is 8192 pixels respectively. For facilitating the FFT calculation process (to be described later), the number of pixels may be set as a power of 2 (e.g., 2 to the 13th power). At this time, the entire image region of the image data Img corresponds to a rectangular region of roughly 82 mm square. 
       FIG. 14B  is an explanatory diagram representing pixel value definitions in the image data Img. For example, it is assumed that the number of gradation levels for each individual pixel is 8 bits (256 gradations). An optical density of zero is set to correspond to a pixel value of zero (lowest value), whereas an optical density of 4.5 is set to correspond to a pixel value of 255 (highest value). For pixel values 1 to 254 therebetween, values are determined according to a linear relationship with respect to the optical density. It goes without saying that the optical density is not limited solely to transmissive density, but may be also reflective density, and can be selected appropriately depending on the manner in which the conductive film  14  is to be used. Further, apart from optical density, tristimulus values XYZ, RGB color values, or L*a*b* color values, etc., can also be used to define respective pixel values, similar to the above description. 
     In this manner, the image data generating unit  38  creates the image data ImgInit corresponding to the mesh pattern M, based on the data definition of the image data Img and the image information estimated by the image information estimating unit  36  (refer to the description of step S 1 ) (step S 22 ). Using a Voronoi diagram as a reference for the initial positions of the seed points SD (see  FIG. 15A ), the image data generating unit  38  determines initial conditions for the mesh pattern M shown in  FIG. 15B . Concerning the end portions of the image, processing is performed so as to repeatedly arrange the same in vertical and horizontal directions. For example, concerning seed points SD in the vicinity of the left end (or right end) of the image, the processing is performed such that regions V i  are obtained between such left-end (or right-end) seed points SD and other seed points SD in the vicinity of the right end (or left end) of the image. Similarly, concerning seed points SD in the vicinity of the upper end (or lower end) of the image, the processing is performed such that regions V i  are obtained between such upper-end (or lower-end) seed points SD and other seed points SD in the vicinity of the lower end (or upper end) of the image. 
     Below, the image data Img is handled as respective 4-channel image data made up of optical density OD, color value L*, color value a*, and color value b*. 
     Next, the mesh pattern evaluating unit  40  calculates the evaluation value EVPInit as an initial value (step S 23 ). In the SA method, the evaluation value EVP assumes the role of a cost function. 
     More specifically, the FFT operating unit  100  shown in  FIG. 4  effects FFT with respect to the image data ImgInit. In addition, the evaluation value calculating unit  102  calculates the evaluation value EVP based on the spectrum Spc supplied from the FFT operating unit  100 . 
     From within the image data Img, evaluation values EVP(L*), EVP(a*), EVP(b*) are calculated respectively for each of the respective channels for the color value L*, the color value a*, and the color value b* (refer to formula (1) above). In addition, the evaluation value EVP is obtained by a product-sum operation using a predetermined weighting coefficient. 
     In place of the color values L*, a*, b*, optical density OD may also be used. In relation to the evaluation value EVP, depending on the type of observational mode, i.e., corresponding to whether the auxiliary light source is predominantly transmissive light, predominantly reflective light, or a mixture of transmissive and reflective light, an appropriate calculation method can be selected that complies with human visual sensitivity. 
     Further, it goes without saying that the formula for computing the evaluation value EVP may be changed corresponding to the target level (acceptable range or tolerance) or the evaluation function for determining the mesh pattern M. 
     In this manner, the mesh pattern evaluating unit  40  calculates the evaluation value EVPInit (step S 23 ). 
     Next, the storage unit  24  temporarily stores the image data ImgInit created in step S 22 , and the evaluation value EVPInit calculated in step S 23  (step S 24 ). Along therewith, an initial value nΔT (where n is a natural number and ΔT is a positive real number) is assigned to the simulated temperature T. 
     Next, the counter  108  initializes the variable K (step S 25 ). That is, the counter  108  assigns 0 to the variable K. 
     Then, in a state in which a portion of the seed points SD (second seed points SDS) are replaced by candidate points SP, and after image data ImgTemp is created as temporary data and evaluation data EVPTemp is calculated as temporary data, a determination is made as to whether to “update” or “not update” the seed points SD (step S 26 ). Further details concerning step S 26  will be described with reference to the flowchart of  FIG. 16  and the functional block diagrams of  FIG. 1  and  FIG. 4 . 
     First, the updated candidate position determining unit  30  extracts and determines candidate points SP from the predetermined two-dimensional image region  200  (step S 261 ). The updated candidate position determining unit  30 , for example, using a random value supplied from the random number generator  26 , determines non-overlapping positions in relation to any of the positions of the seed points SD. The candidate points SP may be a single point or a plurality of points. In the example shown in  FIG. 17A , two candidate points SP (point Q 1  and point Q 2 ) are determined with respect to the eight current seed points SD (points P 1  to P 8 ). 
     Next, a portion of the seed points SD and the candidate points SP are exchanged at random (step S 262 ). The updated candidate position determining unit  30  establishes a correspondence randomly between each of the candidate points SP and each of the exchanged (or updated) seed points SD. In  FIG. 17A , a correspondence is established between point P 1  and point Q 1 , and also between point P 3  and point Q 2 . As shown in  FIG. 17B , the point P 1  and the point Q 1  are exchanged, and the point P 3  and the point Q 2  are exchanged. In this case, points P 2  and points P 4  to P 8 , which are not subject to exchange (or updating), are referred to as first seed points SDN, whereas point P 1  and point P 3 , which are subject to exchange (or updating), are referred to as second seed points SDS. 
     Then, using the exchanged and updated seed points SD (see  FIG. 17B ), the image data generating unit  38  generates the image data ImgTemp (step S 263 ). At this time, the method used is the same as in the case of step S 22  (see  FIG. 10 ) and thus explanations therefor are omitted. 
     Next, the mesh pattern evaluating unit  40  calculates an evaluation value EVPTemp based on the image data ImgTemp (step S 264 ). At this time, the method used is the same as in the case of step S 24  (see  FIG. 10 ) and thus explanations therefor are omitted. 
     Next, the update probability calculation unit  112  calculates an update probability Prob for updating the positions of the seed points SD (step S 265 ). The phrase “updating the positions” implies determining, as new seed points SD, seed points SD that are tentatively exchanged and obtained in step S 262  (i.e., the first seed points SDN and the candidate points SP). 
     More specifically, in accordance with the Metropolis Criterion, a probability of updating the seed points SD and a probability of not updating the seed points SD are calculated. The update probability Prob is given by the following formula (2). 
     
       
         
           
             
               
                 
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     The variable T represents a simulated temperature, wherein, in accordance with the simulated temperature T approaching an absolute temperature (T=0), the updating rule for the seed points SD changes from stochastic to deterministic. 
     Next, in accordance with the update probability Prob calculated by the update probability calculation unit  112 , the position update determining unit  114  determines whether or not to update the positions of the seed points SD (step S 266 ). For example, such a determination may be made stochastically using a random number value supplied from the random number generator  26 . 
     In the case that the seed points SD are to be updated, an “update” instruction is given to the storage unit  24 , whereas in the case that the seed points SD are not to be updated, a “do not update” instruction is given to the storage unit  24  (steps S 267 , S 268 ). 
     In the foregoing manner, step S 26  is brought to an end. 
     Returning to  FIG. 10 , in accordance with either of the instructions “update” or “do not update”, it is determined whether or not the seed points SD should be updated (step S 27 ). In the case that the seed points SD are not updated, step S 29  is not performed and the routine proceeds directly to step S 30 . 
     On the other hand, in the case that the seed points SD are to be updated, in step S 28 , the storage unit  24  overwrites and updates the presently stored image data Img with the image data ImgTemp determined in step S 263  (see  FIG. 16 ). Further, also in step S 28 , the storage unit  24  overwrites and updates the presently stored evaluation value EVP with the evaluation value EVPTemp determined in step S 264 . Furthermore, also in step S 28 , the storage unit  24  overwrites and updates the presently stored position data SDSd of the second seed points SDS with the position data SPd of the candidate points SP determined in step S 261 . Thereafter, the routine proceeds to step S 29 . 
     Next, the counter  108  increments the value of K at the present time by 1 (step S 29 ). 
     Then, the counter  108  compares a magnitude relationship between the value of K at the present time and the predetermined value of Kmax (step S 30 ). If the value of K is smaller than Kmax, then the process returns to step S 26 , and steps S 26  to S 29  thereafter are repeated. In this case, in order to sufficiently ensure convergence at an optimized calculation, the value of Kmax can be set, for example, at Kmax=10000. 
     In cases apart therefrom, the simulated temperature management unit  110  decrements the simulated temperature T by ΔT (step S 31 ) and then proceeds to step S 32 . The change in the simulated temperature T is not limited to being decremented by ΔT, but the simulated temperature T may also be multiplied by a fixed constant δ (0&lt;δ&lt;1). In this case, the update probability Prob (lower) indicated in formula (2) is decremented by a constant value. 
     Next, the simulated temperature management unit  110  determines whether or not, at the present time, the simulated temperature T is equivalent to zero (step S 32 ). If T is not equal to zero, then the process returns to step S 25 , and steps S 25  to S 31  are repeated. 
     On the other hand, if T is equivalent to zero, then the simulated temperature management unit  110  issues a notification to the output image data determining unit  116  to the effect that evaluation of the mesh pattern by the SA method has been completed. In addition, the storage unit  24  overwrites the content of the updated image data Img, which was updated for the last time in step S 28 , onto the output image data ImgOut, thereby updating the same (step S 33 ). 
     In this manner, step S 2  is brought to an end. Thereafter, the output image data ImgOut is supplied to the exposure data conversion unit  32 , and then converted into a control signal for the exposure unit  18 . 
     So that the operator can visually confirm the data, the obtained output image data ImgOut may be displayed on the display device  22 , and the mesh pattern M may be made visual in a simulated manner. Below, an example shall be described of actual visual results of the output image data ImgOut. 
       FIG. 18  is a cross sectional view taken along the X-axis of spectra Spc obtained by effecting FFT respectively on image data representing various types of patterns PT 1  to PT 3  (see  FIGS. 33A to 33C ) according to conventional examples, and the first mesh pattern M 1  according to a present embodiment. 
     The spectrum Spc of the pattern PT 1  shown in  FIG. 33A  has a broad width peak (2 to 30 cycle/mm) with an apex at approximately 10 cycle/mm. Further, the spectrum Spc of the pattern PT 2  shown in  FIG. 33B  has a broad width peak (3 to 20 cycle/mm) centered at approximately 3 cycle/mm. Furthermore, the spectrum Spc of the pattern PT 3  shown in  FIG. 33C  has a comparatively narrow width peak (8 to 18 cycle/mm) centered at approximately 10 cycle/mm. In contrast thereto, the spectrum Spc of the first mesh pattern M 1  has a narrow width peak centered at 8.8 cycle/mm. 
     An explanation shall be given next concerning a relationship between characteristics of the spectrum Spc shown in  FIG. 8C  and centroid positions of the respective meshes. As shown in  FIG. 19 , with respect to a two-dimensional image region  202  similar to that shown in  FIG. 12B , using the aforementioned Voronoi diagram, respective polygonal shaped regions V 1  to V 8  are defined. Points C 1  to C 8  belonging respectively to the regions V 1  to V 8  represent centroid positions of such regions respectively. 
       FIG. 20  is an outline explanatory drawing showing a relationship between plural meshes and centroid positions of the meshes, in relation to the first mesh pattern M 1  according to the present embodiment. 
       FIG. 21A  is an outline explanatory drawing in which image data (hereinafter referred to as “centroid image data Imgc”) are made visible, showing a distribution of centroid positions (hereinafter referred to as a “centroid distribution C”) of respective meshes of the first mesh pattern M 1  of  FIG. 20 . As understood from the drawing, the centroid distribution C is such that the centroid positions are scattered suitably so as not to overlap mutually with each other. 
       FIG. 21B  is a distribution diagram of a two-dimensional spectrum (hereinafter referred to as a “centroid spectrum Spcc”) obtained by effecting FFT with respect to the centroid image data Imgc of  FIG. 21A . The horizontal axis of the distribution diagram shows the spatial frequency with respect to the X-axis direction, whereas the vertical axis thereof shows the spatial frequency with respect to the Y-axis direction. Further, within each spatial frequency band, as the display density becomes thinner, the intensity level (spectral value) becomes smaller, whereas as the display density becomes denser, the intensity level becomes greater. The distribution of the centroid spectrum Spcc is isotropic and exhibits one annular peak. 
       FIG. 21C  is a cross sectional view taken along line XXIC-XXIC of the distribution of the centroid spectrum Spcc shown in  FIG. 21B . Because the centroid spectrum Spcc is isotropic,  FIG. 21C  corresponds to a radial distribution with respect to all angular directions. As understood from the present drawing, the intensity level becomes small in a low spatial frequency band, and has a broad peak in an intermediate spatial frequency band. Furthermore, a so-called high-pass characteristic is exhibited in which, in contrast to low spatial frequency bands, the intensity level is high in high spatial frequency bands. More specifically, according to common technical terminology in the field of image engineering, the centroid image data Imgc shown in  FIG. 21A  is representative of a pattern having a “blue noise” characteristic. 
       FIG. 22  is a comparative drawing illustrating the spectra Spc shown in  FIG. 8C  and the centroid spectrum Spcc shown in  FIG. 21 . More specifically, the spectrum Spc of the first mesh pattern M 1  is compared with the centroid spectrum Spcc of the centroid distribution. For the sake of convenience, intensities of the spectra are normalized so that the maximum peak values PK thereof are in agreement. 
     According to the present drawing, peaks P K  of the spatial frequencies F P  are in agreement, corresponding to a value of 8.8 cycle/mm. In high spatial frequency bands in excess of the spatial frequency F P , the intensity of the spectrum Spc gradually decreases, whereas in contrast thereto, the intensity of the centroid spectrum Spcc is maintained at an even higher value. The reason therefor is presumed to be that, in contrast to the constituent elements of the mesh pattern M being line segments having a predetermined width and which intersect each other, the constituent elements of the centroid distribution are points. 
       FIG. 23  is an outline explanatory drawing representative of characteristics of the centroid spectrum Spcc of  FIG. 21C . The value of the centroid spectrum Spcc increases gradually in a range of 0 to 5 cycle/mm, increases rapidly in the vicinity of 6 cycle/mm, and has a broad peak at roughly 10 cycle/mm. In addition, the value of the centroid spectrum Spcc decreases gradually in a range of 10 to 15 cycle/mm, and is maintained at a high value in high spatial frequency bands in excess of 15 cycle/mm. 
     A standard spatial frequency (predetermined spatial frequency) Fb is set to 6 cycle/mm. Within a range on the side of a spatial frequency band lower than Fb, i.e., within a range from 0 to Fb [cycle/mm], the average value of the centroid spectrum Spcc is set to P L . On the other hand, within a range on the side of a spatial frequency band higher than Fb, i.e., within a range from Fb [cycle/mm] to the Nyquist frequency, the average value of the centroid spectrum Spcc is set to P H . In this manner, the value of P H  is greater than the value of P L . Since the centroid frequency Spcc has such a characteristic, the sensation of noise that is felt visually by an observer is reduced. The basis therefor is as follows. 
     For example, the value of Fb is set so that a spatial frequency results in which the human visual response characteristic corresponds to 5% of the maximum response. Assuming an intensity level is present, the level is such that visibility is difficult. Further, as shown in  FIG. 9 , an acquired visual response characteristic is used based on a Dooley-Shaw function at a visibility distance of 300 mm. The present function is closely compatible with human visual response characteristics. 
     More specifically, as the value Fb in the Dooley-Shaw function at a visibility distance of 300 mm, there can be used a spatial frequency of 6 cycle/mm, which corresponds to 5% of the maximum response. It is further noted that 6 cycle/mm corresponds to an interval of 167 μm. 
     In the present specification, the power spectrum of a centroid position distribution of the mesh pattern M, which is possessed by the conductive film  14 , corresponds with a spectrum obtained by the following process. More specifically, image data ImgOut representing the pattern of the mesh pattern M are acquired, respective meshes (closed spaces) are identified, centroid positions (e.g., one pixel dot) thereof are calculated respectively and centroid image data Imgc are determined, and a two-dimensional power spectrum (centroid spectrum Spcc) thereof is determined, whereby a power spectrum of the centroid position distribution of the mesh pattern M is obtained. Concerning the method for acquiring the image data ImgOut, grayscale image data of the conductive film  14  may be acquired using an input apparatus such as a scanner or the like, or image data ImgOut (see  FIG. 1 ) obtained using the actual output form of the mesh pattern M may be used. 
     Next, with reference to  FIGS. 7 and 24  and the flowchart of  FIG. 25 , an explanation shall be given concerning a method of generating a second mesh pattern M 2 , which is suitable under a condition in which a black matrix  59  (see  FIG. 2B ) is superimposed. 
     In the flowchart of  FIG. 7 , operations of the manufacturing apparatus  10  are basically the same as the case of generating the first mesh pattern M 1 . Upon inputting the various conditions (step S 1 ), not only visual information in relation to visibility of the mesh pattern M, but visual information in relation to the black matrix  59  also are input. 
     The operator inputs appropriate numerical values via the setting screen  160  (see  FIG. 6 ) displayed on the display device  22 . As a result, visual information in relation to visibility of the black matrix  59  can be input. The visible information of the black matrix  59  is defined by various types of information that contribute to the shape and optical density of the black matrix  59 , and includes visual information of the pattern material. As visual information of the pattern material, for example, there are included at least one of a type, a color, an optical transmittance, or an optical reflectance of the pattern material, or an arrangement position, a unit shape, or a unit size of the structural pattern may be included in the visual information of the pattern material. 
     In relation to the black matrix  59  that is to be superimposed, the operator inputs various conditions of the black matrix  59  using the text box  164  shown in  FIG. 6 . 
     The inputs made via the radio buttons  162   a ,  162   b  correspond to whether or not output image data ImgOut is created representing a pattern in which the black matrix  59  is superimposed on the mesh pattern M. In the present case, the black matrix is superimposed, and therefore, the radio button  162   a  (“PRESENCE”) is selected. 
     The value input to the text box  164  randomly determines the arrangement position of the black matrix  59 , and corresponds to the number of trials carried out to generate and evaluate the image data Img. For example, in the event the value is set to 5 times, five instances of superimposed image data are created in which positional relationships are determined between the mesh pattern M and the black matrix  59 , and using respective average values of the evaluation value EVP, evaluation of the pattern of the mesh is carried out. 
     The values of the text boxes  166 ,  168 ,  170 ,  172  correspond to the optical density of the black matrix  59  (units: D), the vertical size of the unit pixel  60  (units: μm), the vertical size of the unit pixel  60  (units: μm), the width of the light-shielding material  61   h  (units: μm), and the width of the light-shielding material  61   v  (units: μm). 
     Furthermore, based on the optical density of the black matrix  59  (text box  166 ), the vertical size of the unit pixel  60  (text box  168 ), the vertical size of the unit pixel  60  (text box  170 ), the width of the light-shielding material  61   h  (text box  172 ), and the width of the light-shielding material  61   v  (text box  174 ), the pattern of the mesh pattern M (i.e., the shape and optical density) in the case that the black matrix  59  is superimposed can be estimated. 
       FIG. 24  is a second flowchart explaining the method of creating output image data ImgOut. Compared with  FIG. 10 , the present figure differs in that a step (step S 22 A) is provided for generating superimposed image data ImgInit′. Further, a feature (step S 26 A) in which it is determined from later-described superimposed image data ImgTemp′ whether to update or not update the seed points SD differs from step S 26  (see  FIG. 10 ). The other steps S 21  through S 25 , and S 27  through S 33  are the same as already described above, and thus explanation of the operations of such steps is omitted. 
     In step S 22 A, the image data generating unit  38  generates superimposed image data ImgInit′ based on the image data ImgInit generated in step S 22  and image information of the black matrix  59  estimated by the image information estimating unit  36  (refer to the explanation of step S 1 ). The superimposed image data ImgInit is image data representative of a pattern in which a black matrix  59  as a structural pattern is superimposed on the second mesh pattern M 2 . 
     In the case that the data definitions for pixel values of the image data ImgInit are indicative of transmission density, the transmission density (the value input to the text box  166  in  FIG. 6 ) of each of the pixels is added corresponding to the arrangement position of the black matrix  59 , and the superimposed image data ImgInit′ can be generated. Further, in the case that the data definitions for pixel values of the image data ImgInit are indicative of reflection density, the reflection density (the value input to the same text box  166 ) of each of the pixels is substituted therefor corresponding to the arrangement position of the black matrix  59 , and the superimposed image data ImgInit′ can be generated. 
     In step S 26 A, in a condition in which a portion of the seed points SD (second seed points SDS) are replaced by candidate points SP, superimposed image data ImgTemp′ is generated, and after the evaluation value EVPTemp is calculated, a determination is made as to whether to “update” or “not update” the seed points SD. 
     The flowchart of  FIG. 25 , in comparison with  FIG. 16 , differs in that a step (step S 263 A) is provided for generating superimposed image data ImgTemp′. The other steps S 261  through S 268  are the same as already described above, and thus explanation of the operations of such steps is omitted. 
     In step S 263 A, the image data generating unit  38  generates superimposed image data ImgTemp′ based on the image data ImgTemp generated in step S 263  and image information of the black matrix  59  estimated by the image information estimating unit  36  (refer to the explanation of step S 1 ). At this time, the method used is the same as in the case of step S 22 A (see  FIG. 24 ) and thus explanations therefor are omitted. 
     In this manner, in addition to generating the superimposed image data ImgTemp′ (or the superimposed image data ImgInit′), by calculating the evaluation data EVP (or the evaluation data EVPInit), the mesh shape can be evaluated taking into consideration the pattern of the black matrix  59 . 
     In the foregoing manner, step S 2 A is brought to an end. Thereafter, the output image data ImgOut is supplied to the exposure data conversion unit  32 , in order to produce image data that is converted into a control signal for the exposure unit  18 . 
       FIG. 26A  is a visual outline explanatory drawing in which a black matrix  59  is superimposed on output image data ImgOut representative of the pattern of the conductive film  14 . The second mesh pattern M 2 , a red filter  58   r , a green filter  58   g , a blue filter  58   b , and the black matrix  59  are shown respectively so as to enable them to be distinguished from each other. 
       FIGS. 26B through 26D  are graphs representing results in which R-component, G-component, and B-component color values within the image data ImgOut of  FIG. 26A  are extracted respectively and spectra Spc are calculated therefrom. As shown in  FIGS. 26B to 26D , spectra Spc are obtained which are substantially the same for each of the RGB components. In any of such spectra, noise peaks are generated centered about spatial frequencies corresponding to the arrangement interval of the light shielding materials  61   h ,  61   v  of the black matrix  59 . 
     In contrast thereto,  FIG. 27A  is a visual outline explanatory drawing in which human visual response characteristics are applied with respect to the output image data ImgOut of  FIG. 26A . By applying human visual response characteristics, or stated otherwise, by applying a low-pass filter (see  FIG. 9 ), fine structural contours of the second mesh pattern M 2  and the black matrix  59  are rendered almost visually imperceptible. 
       FIGS. 27B through 27D  are graphs representing results in which R-component, G-component, and B-component color values within the image data of  FIG. 27A  are extracted respectively and power spectra Spcv are calculated therefrom. Compared with  FIG. 26A , the aforementioned peak noise characteristics are shifted toward the low spatial frequency side, together with reducing the area formed by the spectra Spcv. 
     Using such a method, concerning noise characteristics of the second mesh pattern M 2  on which the black matrix  59  is superimposed, an evaluation can be performed which conforms more closely to human visual response characteristics. 
       FIG. 28A  is an outline explanatory view in which a second mesh pattern M 2  is made visual, which is representative of the pattern of the conductive film  14 , using output image data ImgOut optimized under conditions of not being superimposed with the black matrix  59 .  FIG. 28B  is an outline explanatory view in which the second mesh pattern M 2  is made visual, which is representative of the pattern of the conductive film  14 , using output image data ImgOut optimized under conditions of being superimposed with the black matrix  59 . 
     As can be understood from  FIGS. 28A and 28B , compared to the pattern of the mesh pattern M 1 , the pattern (each of the openings  52 ) of the mesh pattern M 2  has a laterally elongate shape as a whole. The basis therefore is estimated in the following manner. 
     For example, the shape of the unit pixels  60  of the black matrix  59  shown in  FIG. 2B  is assumed to be square. By arranging the red filters  58   r , green filters  58   g , and blue filters  58   b  in a horizontal direction, the unit pixels  60  are partitioned into regions that are ⅓ the size of the unit pixels  60 , whereby noise granularity of high spatial frequency components increases. On the other hand, in the vertical direction, only spatial frequency components exist that correspond to the period at which the light shielding materials  61   h  are disposed, and so that spatial frequency components apart therefrom do not exist, the pattern of the mesh pattern M 2  is determined such that visibility of the arrangement period is low. In other words, respective wires that extend in the horizontal direction are determined so that the intervals therebetween are as narrow as possible, and the wires are arranged regularly between the respective light shielding materials  61   h.    
     In this manner, by superimposing the black matrix  59  (structural pattern) and creating the image data Img (including output image data ImgOut), the mesh shape can be optimized taking into consideration the pattern of the black matrix  59 . 
     Returning to  FIG. 7 , the exposure unit  18  carries out an exposure process for the mesh pattern M (step S 3 ), and thereafter, a development treatment is performed (step S 4 ). 
     Several methods (first through fourth methods) for producing mesh patterns M from metallic thin wires  54  disposed on the transparent film substrate  56  will be described below with reference to  FIGS. 29A to 32 . 
     In the first method, a photosensitive silver salt layer is exposed, developed, and fixed on the transparent film substrate  56  to form metallic silver portions. The metallic silver portions are utilized for constituting the mesh pattern M. 
     More specifically, as shown in  FIG. 29A , the transparent film substrate  56  is coated with a photosensitive silver salt layer  66  containing a mixture of a gelatin  64  and a silver halide  62  (e.g., silver bromide particles, silver chlorobromide particles, or silver iodobromide particles). Although the silver halide  62  is exaggeratingly shown by points in  FIGS. 29A to 29C  to facilitate understanding, the points do not represent the size, concentration, etc. 
     Thereafter, as shown in  FIG. 29B , the photosensitive silver salt layer  66  is subjected to an exposure treatment required for forming the conductive portion  50 . More specifically, the photosensitive silver salt layer  66  is irradiated with the light  16  via a mask pattern that corresponds to an exposure pattern obtained through the pattern generating process shown in  FIG. 10  or  FIG. 24 . Alternatively, an exposure pattern generated by the pattern generating process exposes the photosensitive silver salt layer  66  in accordance with digital writing exposure applied with respect to the photosensitive silver salt layer  66 . If optical energy is applied to the silver halide  62 , the silver halide  62  is exposed to generate minute silver nuclei therein, referred to as a “latent image”, which are not observable to the naked eye. 
     Then, as shown in  FIG. 29C , the photosensitive silver salt layer  66  is subjected to a development treatment for converting the latent image into a visible image observable to the naked eye. More specifically, the photosensitive silver salt layer  66  having the latent image is developed using a developer (i.e., an alkaline or acidic solution, generally an alkaline solution). In the development treatment, using the latent image silver nuclei as catalyst cores, silver ions from the silver halide particles or the developer are reduced to metallic silver by a reducing agent in the developer (referred to as a developing agent). As a result, the latent image silver nuclei are grown to form a visible silver image (developed silver  68 ). 
     The silver halide  62  remains in the photosensitive silver salt layer  66  after the development treatment. As shown in  FIG. 29D , the silver halide  62  is removed by a fixation treatment using a fixer (an acidic or alkaline solution, generally an acidic solution). 
     After the fixation treatment, metallic silver portions  70  are formed in exposed areas, and light-transmitting portions  72  containing only the gelatin  64  are formed in unexposed areas. Thus, a combination of the metallic silver portions  70  and the light-transmitting portions  72  is formed on the transparent film substrate  56 , to thereby form the mesh pattern M. 
     In the case that silver bromide is used as the silver halide  62  and a thiosulfate salt is used in the fixation treatment, a reaction represented by the following formula proceeds in the treatment.
 
AgBr (solid)+2S 2 O 3  ions→Ag(S 2 O 3 ) 2  (readily-water-soluble complex)
 
     More specifically, two thiosulfate S 2 O 3  ions and one silver ion in the gelatin  64  (a silver ion from AgBr) are reacted to generate a silver thiosulfate complex. The silver thiosulfate complex has a high water solubility, and thereby is eluted from the gelatin  64 . As a result, the developed silver  68  is fixed and remains as metallic silver portions  70 . The mesh pattern M is constituted by the metallic silver portions  70 . 
     Thus, in the development treatment, the latent image is reacted with the reducing agent to deposit the developed silver  68 , and in the fixation treatment, the residual silver halide  62 , which is not converted into developed silver  68 , is eluted into water. The treatments are described in detail in T. H. James, “The Theory of the Photographic Process, 4th ed.”, Macmillian Publishing Co., Inc., NY, Chapter 15, pp. 438-442, 1977. 
     The development treatment generally is carried out using an alkaline solution. The alkaline solution used in the development treatment may be mixed into the fixer (generally an acidic solution), whereby the activity of the fixer may disadvantageously be changed during the fixation treatment. Further, the developer may remain on the film after removing the film from the development bath, whereby an undesired development reaction may be accelerated by the developer. Thus, it is preferred that the photosensitive silver salt layer  66  is neutralized or acidified by a quencher such as an acetic acid (vinegar) solution after the development treatment and before the fixation treatment. 
     In addition, as shown in  FIG. 29E , a conductive metal  74  may be disposed only on the metallic silver portions  70  by a plating treatment (such as an electroless plating treatment, an electroplating treatment, or a combination thereof), etc. In this case, the mesh pattern M is formed by the metallic silver portions  70  and the conductive metal  74  disposed on the metallic silver portions  70 . 
     Differences between the above mentioned process using the photosensitive silver salt layer  66  (silver salt photography technology) and a process using a photoresist (resist technology) will be described below. 
     In resist technology, a photopolymerization initiator absorbs light in an exposure treatment to initiate a reaction, a photoresist film (a resin) per se undergoes a polymerization reaction to increase or decrease the solubility in a developer, and the resin in an exposed or unexposed area is removed in a development treatment. The developer liquid used in resist technology may be an alkaline solution free of reducing agents, in which an unreacted resin component can be dissolved. On the other hand, as described above, in silver salt photography technology according to the present invention, the minute silver nuclei, i.e., the so-called “latent image”, are formed from silver ions and photoelectrons generated in the silver halide  62  exposed in the exposure treatment. The latent image silver nuclei are grown to form the visible silver image in the development treatment using the developer, which must contain the reducing agent (the developing agent). Thus, resist technology and silver salt photography technology are significantly different in terms of the reactions in the exposure and development treatments. 
     In the development treatment of the resist technology, the unpolymerized resin portion in the exposed or unexposed area is removed. On the other hand, in the development treatment of the silver salt photography technology, using the latent image as the catalyst core, the reduction reaction is conducted by the reducing agent contained in the developer (the developing agent), and the developed silver  68  is grown into a visible size. The gelatin  64  in the unexposed area is not removed. Thus, resist technology and silver salt photography technology are significantly different also in the reactions in the development treatments. 
     The silver halide  62  contained in the gelatin  64  in the unexposed area is eluted in the following fixation treatment, and the gelatin  64  itself is not removed. 
     In this manner, in silver salt photography technology, the main reaction component (the main photosensitive component) is the silver halide, while in resist technology, the main reaction component is the photopolymerization initiator. Further, in the development treatment, the binder (the gelatin  64 ) remains in silver salt photography technology, while the binder is removed in resist technology. Thus, resist technology and silver salt photography technology are significantly different concerning these points. 
     In another method (second production method), for example, as shown in  FIG. 30A , a photoresist film  76  is formed on a copper foil  75  disposed on the transparent film substrate  56  in order to obtain a photosensitive material. Thereafter, exposure is carried out with respect to the photosensitive material. More specifically, the photoresist film  76  is irradiated with light via a mask pattern corresponding to an exposure pattern obtained by the pattern generation process shown in  FIG. 10  or  FIG. 24 . Alternatively, by digital writing exposure carried out with respect to the photoresist film  76 , an exposure pattern created by a pattern generating device is applied to expose the photoresist film  76 . Thereafter, by means of a development treatment, a resist pattern  78  corresponding to the conductive portion  50  is formed on the transparent film substrate  56 , and as shown in  FIG. 30B , etching is carried out on a copper foil  75  exposed from the resist pattern  78 . At this stage, the conductive portion (mesh pattern M) is formed by the copper foil  75  on the transparent film substrate  56 . 
     Further, in the third production method, as shown in  FIG. 31A , a paste  80  containing fine metal particles is printed on the transparent film substrate  56 . As shown in  FIG. 31B , the printed paste  80  may be plated with a metal  82  to form the conductive portion  50  (mesh pattern M). 
     Alternatively, in the fourth production method, as shown in  FIG. 32 , a metallic thin film  84  may be printed on the transparent film substrate  56  by using a screen or gravure printing plate to thereby form the mesh pattern M. 
     Next, in the conductive film  14  according to the present embodiment, a particularly preferred manufacturing method of forming a conductive metal film using a photographic photosensitive silver halide material for the conductive film  14  will mainly be described below. 
     As described above, the conductive film  14  according to the present embodiment may be produced as follows. A photosensitive material having the transparent film substrate  56  and thereon a photosensitive silver halide-containing emulsion layer is exposed and developed, whereby the metallic silver portions  70  and the light-transmitting portions  72  are formed respectively in the exposed areas and the unexposed areas. The metallic silver portions  70  may be subjected to a physical development treatment and/or a plating treatment to deposit the conductive metal  74  thereon. 
     The method for forming the conductive film  14  according to the present embodiment includes the following three processes, depending on the photosensitive materials and development treatments. 
     (1) A process comprising subjecting a photosensitive black-and-white silver halide material free of physical development nuclei to a chemical or physical development, to form the metallic silver portions  70  on the photosensitive material. 
     (2) A process comprising subjecting a photosensitive black-and-white silver halide material having a silver halide emulsion layer containing physical development nuclei to a physical development, to form the metallic silver portions  70  on the photosensitive material. 
     (3) A process comprising subjecting a stack of a photosensitive black-and-white silver halide material free of physical development nuclei and an image-receiving sheet having a non-photosensitive layer containing physical development nuclei to a diffusion transfer development, to form the metallic silver portions  70  on the non-photosensitive image-receiving sheet. 
     In process (1), an integral black-and-white development procedure is used to form a transmittable conductive film such as a transmittable electromagnetic-shielding film or a light-transmitting conductive film on the photosensitive material. The resulting silver is a chemically or physically developed silver containing a high-specific surface area filament, and thereby shows a high activity in the following plating or physical development treatment. 
     In process (2), the silver halide is melted around the physical development nuclei and deposited on the nuclei in the exposed areas, to form a transmittable conductive film on the photosensitive material. Also in this process, an integral black-and-white development procedure is used. Although high activity can be achieved since the silver halide is deposited on the physical development nuclei during development, the developed silver has a spherical shape with small specific surface. 
     In process (3), the silver halide is melted in unexposed areas, and diffused and deposited on the development nuclei of the image-receiving sheet, to form a transmittable conductive film on the sheet. In this process, a so-called separate-type procedure is used, and the image-receiving sheet is peeled off from the photosensitive material. 
     A negative or reversal development treatment can be used in the foregoing processes. In the diffusion transfer development, the negative development treatment can be carried out using an auto-positive photosensitive material. 
     The chemical development, thermal development, solution physical development, and diffusion transfer development have the meanings generally known in the art, and are explained in common photographic chemistry texts such as Shin-ichi Kikuchi, “Shashin Kagaku (Photographic Chemistry)”, Kyoritsu Shuppan Co., Ltd., 1955 and C. E. K. Mees, “The Theory of Photographic Processes, 4th ed.”, MacMillan, 1977. A liquid treatment is generally used in the present invention, and also a thermal development treatment can be utilized. For example, techniques described in Japanese Laid-Open Patent Publication Nos. 2004-184693, 2004-334077, and 2005-010752, and Japanese Patent Application Nos. 2004-244080 and 2004-085655 can be used in the present invention. 
     (Photosensitive Material) 
     A photosensitive material (photosensitive web) as a plating material, for example, is an elongate flexible substrate on which a silver salt-containing layer containing a silver salt (e.g., silver halide) is disposed on the transparent film substrate  56 . Further, a protective layer may be disposed on a silver salt-containing layer. The protective layer implies a layer made up from a binder, for example, such as gelatin or a high-molecular polymer, which may be formed on the silver salt-containing layer for realizing an effect of improving mechanical characteristics or preventing abrasion. The thickness of the protective layer preferably is from 0.02 to 20 μm. 
     Concerning the composition or the like of the silver salt-containing layer and the protective layer, there can be appropriately applied a silver halide emulsion layer (silver salt-containing layer) and the protective layer, which may be applied to a silver halide photographic film, photographic paper, a printing plate film, an emulsion mask for a photomask or the like. 
     In particular, as the photosensitive material, preferably, a silver halide photographic film (silver halide photosensitive material), and more preferably, a black-and-white silver halide photographic film (black-and-white silver halide photosensitive material) is used. Further, as the silver salt applied to the silver salt-containing layer, in particular, silver halide is considered most preferable. The width of the photosensitive material, for example, is 20 cm or greater, and the thickness thereof preferably is 50 to 200 μm. 
     [Transparent Film Substrate  56 ] 
     A flexible plastic film can be used as the transparent film substrate  56  in the manufacturing method of the present embodiment. 
     As raw materials for the above-mentioned flexible plastic film, there can be used, for example, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyolefins such as polyvinyl chloride, polyvinylidene chloride, polyvinyl butyral, polyamide, polyether, polysulfone, polyether sulfone, polycarbonate, polyarylate, polyetherimide, polyether ketone, polyether ether ketone, EVA, etc., polycarbonate, triacetyl cellulose (TAC), acrylic resin, polyimide or aramid. 
     In the present embodiment, from the standpoints of light-transmission, heat resistance, ease of handling, and price, preferably, the aforementioned plastic film is a polyethylene terephthalate (PET) film or a triacetyl cellulose (TAC) film. 
     Since transparency is a required property of a transparent heating element such as window glass or the like, preferably, the transparency of the transparent film substrate  56  is high. In this case, preferably, the total visible optical transmittance of the plastic film is 70% to 100%, more preferably, is 85% to 100%, and still more preferably, is 90% to 100%. Further, with the present invention, a colored or tinted film may be used as the plastic film insofar as the objects of the present invention are not interfered with. 
     The plastic film in the present embodiment can be utilized as a single layer, or can be used as a multilayer film in which two or more layers are combined. 
     [Protective Layer] 
     As for the photosensitive material that is used, the protective layer may be disposed on a later-described emulsion layer. In the present embodiment, the term “protective layer” implies a layer made up from a binder, for example, such as gelatin or a high-molecular polymer, and for realizing an effect of improving mechanical characteristics or preventing abrasion, a photosensitive emulsion layer is formed. The protective layer preferably is not applied by a plating process, and even if provided, a thin protective layer is preferable. The thickness of the protective layer preferably is 0.2 μm or less. The forming method by coating of the protective layer is not particularly limited, and any known coating method can be selected appropriately. 
     [Emulsion Layer] 
     The photosensitive material used in the production method of this embodiment preferably has the transparent film substrate  56  and thereon the emulsion layer containing the silver salt as a light sensor (the photosensitive silver salt layer  66 ). If needed, in addition to silver salt, the emulsion layer according to the present embodiment may contain a dye, a binder, a solvent, etc. 
     &lt;Silver Salt&gt; 
     The silver salt used in the present embodiment preferably is an inorganic silver salt such as a silver halide. It is particularly preferred that the silver salt is used in the form of particles for the photographic photosensitive silver halide material. Silver halide has an excellent light sensing property. 
     The silver halide, preferably used in the photographic emulsion of the photographic photosensitive silver halide material, will be described below. 
     In the present embodiment, silver halide is preferably used as a light sensor. Silver halide technologies for photographic silver salt films, photographic papers, print engraving films, emulsion masks for photomasking, and the like may be utilized in the present embodiment. 
     The silver halide may contain a halogen element of chlorine, bromine, iodine, or fluorine, and may contain a combination of such elements. For example, the silver halide preferably contains AgCl, AgBr, or AgI, and more preferably contains AgBr or AgCl as a principal component thereof. Also, silver chlorobromide, silver iodochlorobromide, or silver iodobromide preferably is used as the silver halide. More preferably, the silver halide is silver chlorobromide, silver bromide, silver iodochlorobromide, or silver iodobromide, and most preferably, is silver chlorobromide or silver iodochlorobromide having a silver chloride content of 50 mol % or more. 
     The phrase, “silver halide contains AgBr (silver bromide) as a principal component” implies that the mole ratio of bromide ions is 50% or more in the silver halide composition. Silver halide particles that contain AgBr as a principal component thereof may also contain iodide or chloride ions in addition to the bromide ions. 
     The silver halide emulsion used in the present embodiment may contain a metal of Group VIII or VIIB. It is particularly preferred that the silver halide emulsion contains a rhodium compound, an iridium compound, a ruthenium compound, an iron compound, an osmium compound, or the like, to obtain a gradation of 4 or more and to achieve low fogging. 
     Also for attaining high sensitivity, doping is advantageously employed with a hexacyano metal complex such as K 4 [Fe(CN) 6 ], K 4 [Ru(CN) 6 ], or K 3 [Cr(CN) 6 ]. 
     The added amount of the above compounds preferably is 10 −10  to 10 −2  mol/mol-Ag, and more preferably, is 10 −9  to 10 −3  mol/mol-Ag per 1 mol of silver halide. 
     Further, in the present embodiment, the silver halide preferably contains Pd (II) ion and/or Pd metal. Pd is preferably contained in the vicinity of the surface of the silver halide particle, although Pd may be uniformly distributed therein. Herein, the phrase “Pd is contained in the vicinity of the surface of the silver halide particle” implies that the particle has a layer with a higher palladium content in a region of 50 nm or less in the depth direction from the surface. 
     Such silver halide particles can be prepared by adding Pd during particle formation thereof. Preferably, Pd is added after the silver ions and the halogen ions have been added respectively at an amount of 50% or more of the total amount. It also is preferred that Pd(II) ions are added in a post-ripening process so that Pd(II) ions exist in the silver halide surface layer. 
     The Pd-containing silver halide particles act to accelerate physical development and non-electrolytic plating, to improve production efficiency of the desired heating element, and to lower production costs. Pd is well known and used as a non-electrolytic plating catalyst. In the present invention, since Pd can be located in the vicinity of the surface of the silver halide particles, the amount of Pd, which is quite expensive, can be reduced. 
     In the present embodiment, the Pd ions and/or Pd metal content with respect to the molar number of silver in the silver halide preferably is 10 −4  to 0.5 mol/mol-Ag, and more preferably, is 0.01 to 0.3 mol/mol-Ag. 
     Examples of Pd compounds used include PdCl 4  and Na 2 PdCl 4 . 
     In the present embodiment, the sensitivity of the light sensor may be further enhanced by chemical sensitization, which is generally used for photographic emulsions. Examples of chemical sensitization methods include chalcogen sensitization methods such as sulfur, selenium, and tellurium sensitization methods, noble metal sensitization methods such as gold sensitization methods, and reduction sensitization methods, or the like. Such methods may be used singly or in combination. In the case of combining the chemical sensitization methods, preferred combinations include a combination of a sulfur sensitization method and a gold sensitization method; a combination of a sulfur sensitization method, a selenium sensitization method, and a gold sensitization method; and a combination of a sulfur sensitization method, a tellurium sensitization method, and a gold sensitization method. 
     &lt;Binder&gt; 
     A binder may be used in the emulsion layer to uniformly disperse the silver salt particles and to assist the emulsion layer in adhering to a support. In the present invention, the binder may contain a water-insoluble or water-soluble polymer, and preferably contains a water-soluble polymer. 
     Examples of the above-discussed binders include gelatins, polyvinyl alcohols (PVA), polyvinyl pyrolidones (PVP), polysaccharides such as starches, celluloses and derivatives thereof, polyethylene oxides, polysaccharides, polyvinylamines, chitosans, polylysines, polyacrylic acids, polyalginic acids, polyhyaluronic acids, and carboxycelluloses. The binders exhibit a neutral, anionic, or cationic property depending on the ionic properties of the functional group. 
     The amount of binder contained in the emulsion layer is not particularly limited, and can be determined suitably within a range capable of exhibiting dispersion and adhesion. For example, the amount preferably is adjusted such that the Ag/binder volume ratio of the photosensitive silver salt layer  66  is ¼ or more, and more preferably, so that the Ag/binder volume ratio is ½ or more. 
     &lt;Solvent&gt; 
     The solvent used for forming the aforementioned emulsion layer is not particularly limited, and examples thereof include water, organic solvents (e.g., alcohols such as methanol, ketones such as acetone, amides such as formamide, sulfoxides such as dimethyl sulfoxide, esters such as ethyl acetate, and ethers, etc.), ionic liquids, as well as mixtures of such solvents. 
     In the present invention, concerning the solvent used in the emulsion layer, the mass ratio of the solvent to the total of the silver salt, the binder, etc., contained in the emulsion layer is 30% to 90% by mass, and more preferably, is 50% to 80% by mass. 
     Next, respective processes for forming the conductive portion  50  (mesh pattern M) shall be explained. 
     [Exposure] 
     In the present embodiment, the photosensitive material having the photosensitive silver salt layer  66  disposed on the transparent film substrate  56  is subjected to an exposure treatment by the exposure unit  18 . Exposure can be carried out using electromagnetic waves. For example, light such as visible light or ultraviolet light, or radiation such as X-rays or the like may be used to generate electromagnetic waves. Exposure may also be carried out using a light source having a wavelength distribution or a specific wavelength. 
     Exposure for forming a pattern image may be carried out using a surface exposure method or a scanning exposure method. In the surface exposure method, the photosensitive surface is irradiated with uniform light through a mask to form an image of a mask pattern. In the scanning exposure method, the photosensitive surface is scanned with a beam of laser light or the like so as to form a patterned irradiated area on the photosensitive surface. 
     Various types of laser beams can be used to carry out exposure. For example, in the present embodiment, scanning exposure preferably can be carried out using monochromatic high-density light of a gas laser, a light-emitting diode, a semiconductor laser, or a second harmonic generation (SHG) light source containing a nonlinear optical crystal in combination with a semiconductor laser or a solid laser using a semiconductor laser as an excitation source. Also, a KrF excimer laser, an ArF excimer laser, an F2 laser, or the like can be used to carry out exposure. To reduce the size and cost of the system, it is preferred that exposure be carried out using a semiconductor laser or a second harmonic generation (SHG) light source containing a nonlinear optical crystal in combination with a semiconductor laser or a solid laser. It is particularly preferred that exposure be carried out using a semiconductor laser, from the standpoint of reducing size and cost, and for improving durability and stability of the apparatus. 
     It is preferred that the photosensitive silver salt layer  66  is exposed to the pattern shape by a scanning exposure method using a laser beam. In particular, a capstan-type laser scanning exposure apparatus, as described in Japanese Laid-Open Patent Publication No. 2000-039677, is preferably used for such an exposure. In a capstan-type apparatus, a DMD as described in Japanese Laid-Open Patent Publication No. 2004-001224 preferably is used in the optical beam scanning system, instead of beam scanning by a rotary polygon mirror. Particularly in the case of producing a long flexible film heater having a length of 3 m or more, it is preferred that the photosensitive material be exposed to a laser beam on a curved exposure stage while the material is conveyed. 
     As described later, the mesh pattern M may be a lattice pattern of a triangle, a quadrangle (e.g., rhombus, square), a hexagon, etc., formed by crossing straight thin wires substantially parallel to each other. Furthermore, the mesh pattern M may be a pattern of straight, zigzag, or wavy wires parallel to each other. No particular limitation is placed thereon, insofar as the mesh pattern M is of a structure that enables a current to flow between electrodes to which a voltage is applied. 
     [Development Treatment] 
     In the present embodiment, after exposure of the emulsion layer, the emulsion layer is further subjected to a development treatment. The development treatment can be performed using common development treatment technologies for photographic silver salt films, photographic papers, print engraving films, emulsion masks for photomasking, and the like. Although not particularly limited, the developer for the development treatment may be a PQ developer, an MQ developer, an MAA developer, etc. Examples of commercially available developers usable in the present invention include CN-16, CR-56, CP45X, FD-3, and PAPITOL, available from FUJIFILM Corporation, and C-41, E-6, RA-4, D-19, and D-72, available from Eastman Kodak Company, as well as other developers contained in kits thereof. 
     The developer may be a lith developer. As one such lith developer, D85 available from Eastman Kodak Company can be used. In the present invention, by performing the aforementioned exposure and development treatments, the metallic silver portion  70 , and preferably the patterned metallic silver portion  70 , is formed in the exposed area, and the light-transmitting portion  72  is formed in the unexposed area. 
     The developer used for the development treatment can contain an image quality improvement agent for improving image quality. Examples of suitable image quality improvement agents can include, for example, nitrogen-containing heterocyclic compounds such as benzotriazole. Further, in the case of using a lith developer, preferably polyethylene glycol is used. 
     The ratio of the metallic silver contained in the exposed portion after development to the silver contained in this portion before exposure preferably is 50% or more, and more preferably, is 80% or more by mass. If the ratio of the silver contained in the exposed portion after development to the silver contained in this portion before exposure is 50% or more by mass, high conductivity can be achieved. 
     In the present embodiment, the gradation obtained by the development preferably is in excess of 4.0, although this value is not particularly limited. If the gradation is in excess of 4.0 after development, conductivity of the conductive metal portion can be increased while maintaining high transmittance of the light-transmitting portion. For example, a gradation of 4.0 or more can be achieved by doping with rhodium or iridium ion. 
     [Physical Development and Plating Treatment] 
     In the present embodiment, to increase conductivity of the metallic silver portion  70  formed by the above exposure and development treatments, conductive metal particles may be deposited on the metallic silver portions  70  by a physical development treatment and/or a plating treatment. In the present embodiment, such conductive metal particles may be deposited on the metallic silver portion  70  by only one of the physical development and plating treatments, or by a combination of such treatments. 
     In the present embodiment, “physical development” is defined by a process in which metal ions such as silver ions are reduced by a reducing agent, whereby the metal particles are deposited on a metal or metal compound core. Such a physical development process has been used in the fields of instant B&amp;W film, instant slide film, printing plate production, etc., and such technologies can also be used in the present invention. 
     [Calendering Treatment] 
     A calendering treatment may be carried out to effect smoothing on the metallic silver portion  70  (i.e., the overall surface of the metallic silver portion, the metallic mesh pattern portion, or the metallic wiring pattern portion). As a result, conductivity of the metallic silver portion  70  can be markedly increased. The calendering treatment can be performed using a calender roll, wherein such a calender roll typically is made up from a pair of rolls. 
     As rolls that are used in the calendering process, plastic rolls of epoxy, polyimide, polyamide, polyimide amide, etc., or metallic rolls are used. In particular, in the case of using an emulsion layers on both surfaces, preferably, processing is carried out by metallic rolls per se. In the case of having an emulsion layer on one side only, from the standpoint of preventing wrinkles, a metallic roll and a plastic roll can be used together in combination. The lower limit value of linear pressure applied by the rolls is 1960 N/cm (200 kgf/cm, or 699.4 kgf/cm 2  if converted to surface pressure) or greater, and more preferably, is 2940 N/cm (300 kgf/cm, or 935.8 kgf/cm 2  if converted to surface pressure) or greater. The upper limit value of linear pressure is 6880 N/cm (700 kgf/cm) or less. 
     The applicable temperature at which the smoothing process represented by calender rollers is carried out preferably is within a range of 10° C. (without temperature adjustment) to 100° C., and more preferably, although it differs depending on the type of binder or the image line density and shape of the metallic mesh pattern or the metallic wiring pattern, is within a range of 10° C. (without temperature adjustment) to 50° C. 
     [Steam Contact Treatment] 
     An advantageous effect can also be brought forth by applying a steam contact treatment together with the calendering treatment immediately prior to or following the calendering treatment. More specifically, conductivity can be enhanced significantly. The temperature of the steam that is used preferably is 80° C. or greater, and more preferably, is 100° C. or higher to 140° C. or less. The contact time during which steam is applied is preferably on the order of from 10 seconds to 5 minutes, and more preferably, is from 1 minute to 5 minutes. 
     In the present invention, the technologies of the following Japanese Laid-Open Patent Publications and PCT International Publication Numbers shown in Tables 1 and 2 can appropriately be used in combination. In the following Tables 1 and 2, conventional notations such as “Japanese Laid-Open Patent Publication No.”, “Publication No.”, “Pamphlet No. WO”, etc., have been omitted. 
     
       
         
               
               
               
               
               
             
           
               
                 TABLE 1 
               
               
                   
               
             
             
               
                 2004-221564 
                 2004-221565 
                 2007-200922 
                 2006-352073 
                 2007-129205 
               
               
                 2007-235115 
                 2007-207987 
                 2006-012935 
                 2006-010795 
                 2006-228469 
               
               
                 2006-332459 
                 2009-21153  
                 2007-226215 
                 2006-261315 
                 2007-072171 
               
               
                 2007-102200 
                 2006-228473 
                 2006-269795 
                 2006-269795 
                 2006-324203 
               
               
                 2006-228478 
                 2006-228836 
                 2007-009326 
                 2006-336090 
                 2006-336099 
               
               
                 2006-348351 
                 2007-270321 
                 2007-270322 
                 2007-201378 
                 2007-335729 
               
               
                 2007-134439 
                 2007-149760 
                 2007-208133 
                 2007-178915 
                 2007-334325 
               
               
                 2007-310091 
                 2007-116137 
                 2007-088219 
                 2007-207883 
                 2007-013130 
               
               
                 2005-302508 
                 2008-218784 
                 2008-227350 
                 2008-227351 
                 2008-244067 
               
               
                 2008-267814 
                 2008-270405 
                 2008-277675 
                 2008-277676 
                 2008-282840 
               
               
                 2008-283029 
                 2008-288305 
                 2008-288419 
                 2008-300720 
                 2008-300721 
               
               
                 2009-4213 
                 2009-10001  
                 2009-16526 
                 2009-21334  
                 2009-26933 
               
               
                 2008-147507 
                 2008-159770 
                 2008-159771 
                 2008-171568 
                 2008-198388 
               
               
                 2008-218096 
                 2008-218264 
                 2008-224916 
                 2008-235224 
                 2008-235467 
               
               
                 2008-241987 
                 2008-251274 
                 2008-251275 
                 2008-252046 
                 2008-277428 
               
               
                   
               
             
          
         
       
     
     
       
         
               
               
               
               
               
             
           
               
                 TABLE 2 
               
               
                   
               
             
             
               
                 2006/001461 
                 2006/088059 
                 2006/098333 
                 2006/098336 
                 2006/098338 
               
               
                 2006/098335 
                 2006/098334 
                 2007/001008 
               
               
                   
               
             
          
         
       
     
     EXAMPLE 
     An example of the present invention will be described more specifically below. Materials, amounts, ratios, treatment contents, treatment procedures, and the like, used in the example may be appropriately changed without departing from the essential scope of the present invention. Therefore, the following specific example should be considered in all respects as illustrative and not restrictive. 
     [Photosensitive Silver Halide Material] 
     An emulsion containing an aqueous medium, gelatin, and silver iodobromochloride particles was prepared. The amount of gelatin was 10.0 g per 60 g of Ag, and the silver iodobromochloride particles had an I content of 0.2 mol %, a Br content of 40 mol %, and an average spherical equivalent diameter of 0.1 μm. 
     K 3 Rh 2 Br 9  and K 2 IrCl 6  were added to the emulsion at a concentration of 10 −7  mol/mol-Ag in order to dope the silver bromide particles with Rh and Ir ions. Na 2 PdCl 4  was further added to the emulsion, and the resultant emulsion was subjected to gold-sulfur sensitization using chlorauric acid and sodium thiosulfate. The emulsion and a gelatin hardening agent were applied to polyethylene terephthalate (PET) such that the amount of the applied silver was 1 g/m 2 . The Ag/gelatin volume ratio was ½. 
     The PET support body had a width of 30 cm, and the emulsion was applied thereto at a width of 25 cm and a length of 20 m. Both end portions of the PET support having a width of 3 cm were cut off in order to obtain a roll-shaped photosensitive silver halide material having a central coating width of 24 cm. 
     [Generation of Exposure Pattern] 
     Using an SA method as described for the present embodiment (see  FIGS. 10 and 24 , etc.), output image data ImgOut representing the first mesh pattern M 1  (see  FIG. 28A ) and the second mesh pattern M 2  (see  FIG. 28B ) and made up from irregularly arranged wirings were created respectively. 
     The set conditions for the first mesh pattern M 1  and the second mesh pattern M 2  were established such that the total transmittance was 93%, the thickness of the transparent film substrate  56  was 20 μm, the width of the metallic thin wires  54  was 20 μm, and the thickness of the metallic thin wires  54  was 10 μm. The pattern size was set to 5 mm both vertically and horizontally, and the image resolution was set to 3500 dpi (dots per inch). Initial positions of the seed points SD were determined randomly using a Mersenne Twister algorithm, and respective polygonal mesh areas were defined using a Voronoi diagram. Evaluation values EVP were calculated based on the L*, a*, b* image data color values of the image data Img. In addition, the same output image data ImgOut were arranged alongside one another in both vertical and horizontal directions to create periodic exposure patterns. 
     On the other hand, the conditions for the black matrix  59  were set such that the optical density was 4.5 D, the unit pixel  60  had a vertical size and a horizontal size of 200 μm, and the widths of the light shielding material  61   h  and the light shielding material  61   v  were both 20 μm. 
     Firstly, the radio button  162   b  on the setting screen  160  of  FIG. 6  was selected, and with “PRESENCE/ABSENCE OF MATRIX” being set to “ABSENCE”, the output image data ImgOut was created. As a result, output image data ImgOut representing the form of the mesh pattern M 1  shown in  FIG. 28A  was obtained. 
     Secondly, the radio button  162   a  on the setting screen  160  of  FIG. 6  was selected, and with “PRESENCE/ABSENCE OF MATRIX” being set to “PRESENCE”, the output image data ImgOut was created. As a result, output image data ImgOut representing the pattern of the mesh pattern M 2  shown in  FIG. 28B  was obtained. 
     [Exposure] 
     Exposure was performed in a continuous exposure apparatus in which exposure heads using a DMD (Digital Mirror Device), as described in the embodiment of the invention described in Japanese Laid-Open Patent Publication No. 2004-001224, were arranged at a width of 25 cm, the exposure heads and an exposure stage were disposed in a curved position so that laser light could form an image on the photosensitive layer of the photosensitive material, a photosensitive material-delivering mechanism and a photosensitive material-winding mechanism were installed, and a bent portion was provided to exhibit a buffering action, so that variations of speed of the tension-controlling mechanism for the exposure surface and the delivering and winding mechanisms did not affect the speed of exposed portions. The wavelength of exposure light was 400 nm, the beam shape was approximately the square of 12 μm, and the irradiation amount of the laser light source was 100 μJ. 
     [Formulation of Developing Solution] 
     The following chemical compounds were included in 1 liter of the developing solution. 
                                                 Hydroquinone   20 g           Sodium sulfite   50 g           Potassium carbonate   40 g           Ethylenediaminetetraacetic acid    2 g           Potassium bromide    3 g           Polyethylene glycol 2000    1 g           Potassium hydroxide    4 g           pH   controlled at 10.3                        
[Formulation of Fixing Solution]
 
     The following chemical compounds were included in 1 liter of the fixing solution. 
                                                                   Ammonium thiosulfate solution (75%)    300    ml           Ammonium sulfite monohydrate   25    g           1,3-Diaminopropanetetraacetic acid   8    g           Acetic acid   5    g           Aqueous ammonia (27%)   1    g                pH   controlled at 6.2                        
[Development Treatment]
 
     Using the treatment agents as listed above, a development treatment was conducted on the photosensitive material following exposure thereof using an automatic development machine FG-710 PTS (manufactured by FUJIFILM Corporation) under the following development conditions; development: 30 seconds at 35° C., fixation: 23 seconds at 34° C., water washing: 20 seconds under running water (5 L/min). 
     As a running process, 100 m 2 /day of the photosensitive material was developed for 3 days while supplying 500 ml/m 2  of a developer replenisher, and 640 ml/m 2  of the fixing solution. At this time, following a plating process, the copper pattern was confirmed to have a line width of 12 μm and a pitch of 300 microns. 
     Further, electroless copper plating was conducted at 45° C. by using a plating solution (a electroless copper plating solution containing 0.06 mol/L of copper sulfate, 0.22 mol/L of formalin, 0.12 mol/L of triethanolamine, 100 ppm of polyethylene glycol, 50 ppm of yellow prussiate of potash and 20 ppm of α,α′-bipyridine, pH=12.5) followed by an oxidation process with an aqueous solution containing 10 ppm of Fe(III) ions, to thereby obtain various samples. 
     Below, the conductive film  14  having the first mesh pattern M 1  is referred to as a first sample, and the conductive film  14  having the second mesh pattern M 1  is referred to as a second sample. Conductive films  14  having patterns PT 1  to PT 3  are referred to as third through fifth samples. 
     [Evaluation] 
     (Measurement of Surface Resistivity) 
     To evaluate uniformity in surface resistivity, surface resistivities of the conductive films  14  were measured at ten arbitrary sites using LORESTA GP (Model MCP-T610) inline 4-pin probe type (ASP), manufactured by Dia Instruments Co., Ltd., to obtain an average value of the surface resistivities. 
     (Evaluation of Noise Sensation) 
     A commercially available color liquid crystal display (screen size: 4.7 type, 640×480 dots) was used. A touch panel on which the first and second samples were adhered was incorporated into the liquid crystal display, an LED lamp as auxiliary light was lit up from a back surface of a liquid crystal panel, the display screen was observed, and a visual evaluation of noise sensation was carried out. Visual confirmation of such noise was carried out from the front side of the liquid crystal panel at an observation distance of 300 mm. 
     [Results] 
     Ten sheets of first through fifth samples having levels sufficiently practical as transparent electrodes and in terms of surface resistivity, and with good transparency, were realized. In particular, the fourth and fifth samples (conductive film  14  according to the present invention) exhibited the lowest variance in surface resistivity. 
     In relation to visibility of noise, successively highest evaluation values were obtained in order of the first sample, the second sample, the fifth sample, the third sample, and the fourth sample. Such an order matches with the order in which the areas exhibited by the peaks of the spectra Spc illustrated in  FIG. 18  become successively larger. In particular, it was confirmed that the sensation of noise exhibited by the first sample (conductive film  14  according to the present invention) was hardly noticeable at all. 
     Furthermore, using a transparent substrate instead of the liquid crystal panel, light across the aforementioned LED lamp was observed, and a similar visual evaluation was carried out, whereby it was confirmed that in the case of the first sample, the sensation of noise was considerably less noticeable than in the case of the second sample. More specifically, it was appreciated that the pattern of the mesh pattern M could be optimized responsive to the visual aspects of the conductive film  14  (e.g., color filters such as the red filters  58   r  or the like, and presence or absence of the black matrix  59 ). 
     In this manner, a plurality of positions (seed points SD) are selected from within a predetermined two-dimensional image region  200 , and based on the selected positions (seed points SD), image data Img are created representing the pattern of a mesh pattern M, and further based on the created image data Img, an evaluation value EVP obtained by quantifying noise characteristics of the mesh pattern M is calculated. Then, based on the calculated evaluation value EVP and predetermined evaluation conditions, one of the image data Img is determined as output image data ImgOut, and based on the determined output image data ImgOut, a wire material is output and formed on the transparent film substrate  56 . Therefore, the shape of a mesh pattern M having noise characteristics that satisfy the predetermined evaluation conditions can be determined. Stated otherwise, by appropriately controlling the noise characteristics of the mesh pattern M, the sensation of noise can be reduced. 
     Further, a mesh pattern M is formed such that, in relation to the centroid spectra Spcc of respective meshes, an average intensity P H  on the side of a spatial frequency band higher than a predetermined spatial frequency Fb is made greater than an average intensity P L  on the side of a spatial frequency band lower than the predetermined spatial frequency Fb. Thus, compared to the low spatial frequency band side, the amount of noise on the side of the high spatial frequency band is relatively large. Human vision exhibits a property in which the response characteristic thereof is high in low spatial frequency bands, whereas in mid to high spatial frequency bands, the response characteristic rapidly decreases, and thus, the sensation of noise as perceived visually by humans decreases. Owing thereto, granular noise caused by the pattern possessed by the conductive film  14  can be lowered, whereby visibility of objects to be observed can be significantly enhanced. Further, because a plurality of polygonal meshes are provided, the cross sectional shape of the respective wires (metallic thin wires  54 ) after cutting is substantially constant, and thus stable power performance is exhibited. 
     The present invention is not limited to the embodiment described above, but various changes and modifications may be made without departing from the scope of the invention. 
     The pattern material is not limited to being a black matrix, and it goes without saying that, responsive to the various uses thereof, the present invention can be applied with respect to structural patterns of various shapes.