Abstract:
An optical imaging system for producing and applying image masks consisting of an original object holder, an image forming optical system, recording means for the image formed, processing means for the recorded image, means for maintaining the recorded image in precise register with the original object. The recorded image is projected back on the original in a modified form by means of adding and controlling optical flare in the imaging system to control image contract and by well known means control image color and sharpness. This modified projected image in register with the original objects acts as a mask for image enhancement. The resulting enhanced image can then be recorded by photographic film or paper and other ray recording devices.

Description:
BACKGROUND AND OBJECTS OF THE INVENTION 
     This invention is an improvement of my invention U.S. Pat. No. 4,422,753 dated Dec. 27, 1983 and filed Nov. 25, 1981 entitled &#34;Multichannel Masking Camera and Projector.&#34; This present invention is a simplification of the previous invention and is limited in application to the controlled masking or combination of a single image by another image. It can be used in an optical printer for motion pictures, a photographic enlarger or a transparency copier. The introductory comments regarding masking etc, in my invention U.S. Pat. No. 4,422,753 also apply to this invention. Other similarities and differences will become apparent. (Other references in this application are U.S. Pat. Nos. 3,085,469, 2,354,108, 3,912,361. 
     Although my invention U.S. Pat. No. 4,422,753 overcomes many difficulties and inconveniences of previous masking techniques and devices and is cheaper to produce and operate than many electro-optical approaches to photo-image control and enhancement--it can be further simplified and improved to speed up the operation as shown in this invention. 
     These improvements embodied in this invention are applicable to the production of contrast controlled reproduction, edge enhancement, subtractive image combination and similar effects. Multi-channel effects such as controlled image combinations in which each channel require masking or control, multi color masking control, etc, which require more than one masking channel will still be better performed with a multi channel masking systems as described in my U.S. Pat. No. 4,422,753. 
     An object of the present invention is to provide a method of and an improved image enhancement apparatus for use in producing improved enhanced photography and cinematography. 
     Another object of this invention is to provide a simpler method of and an apparatus for controlling the contrast and edge enhancement of images while one is observing the results of the modification before recording the resulting image in an enlarger, transparency duplicator or cinematographic optical printer. 
     Still another object of this invention is to provide in an optical system, with a means of controlling image contrast by Flare or Vieling glare control. 
     A further object of this invention is to provide an in-situ development device for use in camera-projector systems. 
     Other objects and advantages will appear as the following detailed description proceeds. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a diagrammatic view of a simple one channel form of the Masking Camera Projector embodying principles of my improved invention which apparatus may be used in practicing my invention. 
     FIG. 2 is an exploded view of an improved film holder incorporating one type of &#34;In-Situ Development&#34;. 
     FIG. 3 is a plan view of assembled film holder in FIG. 2. 
     FIG. 4 is a cross section of FIG. 3 at 4--4. 
     FIG. 5 is a plan view of an insert for the imaging lens 4 in FIG. 1 illustrating a flare control device and technique. 
     FIG. 6 is a plan view of the imaging lens in FIG. 4 illustrating an alternate means of flare control. 
     FIG. 7 is another diagrammatic view of a simple one channel form of the Masking Camera Projector embodying alternate optional means for implementing the principles illustrated in FIG. 1. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     This invention relates to methods of and devices for producing and combining transparent images in precise registration so as to improve and enchance the final image. For example, combining a negative or positive image of a positive transparency original in register with the original positive to reduce or increase contrast and improve the rendition of fine detail. As in my original invention U.S. Pat. No. 4,422,753 other usages will become obvious to one skilled in the art as the description proceeds. The differences between this invention and the original invention will also become obvious as will its advantages of simplicity, cheapness and convenience of operation. For one embodiment of this invention an improved single channel system the arrangements of parts and their operation will now be explained. Referring to FIG. 1, we note that there is no mirror or beam splitter as in my invention U.S. Pat. No. 4,422,753. As in my original invention at position 1 we have the original transparency which we wish to modify or improve. This transparency 1 is illuminated for purposes of imaging and recording at location 2 by light source 3. The image forming optical system between 1 and 2 can be treated as one system composed of several elements and components to produce a controlled image of 1 at 2 or 2 at 1. This optical system can be incorporated in the well known motion picture optical printer, in addition to its usual optics, to improve the operation and performance thereof. Some of the controlled functions of this optical system are described as follows. The principle image forming power is represented by elements at 4 with images 1 and 2 at the corresponding focal positions. Optical element 5 near focal plane at 1 is representative of a field lens used when reimaging the image of 2 combined with object at 1 for final recording with system represented by 6 which would replace light source 3 when final recording is required. Glass plates 7 represent one method whereby the optical system can be controlled to change the size and sharpness of images produced at 1 and 2. This can be accomplished by the insertion and or removal of either or both plates. 8 represents an optical color filter which can be used to control the colors of the image formed at 2 or 1. 9 represent a diffusion filter or other method of controlling the flare in the optical system between 1 and 2. An alternate method of controlling flare is shown in FIGS. 5 and 6 and as set forth in the following discussion. It has therefore been shown how the optical systems between 1 and 2 can not only image 1 at 2 or 2 at 1, but provide for color control, sharpness control, and constrast control of the images formed. The optical system also provides for even illumination (by means of a field lens) when the combined image at 1 is recorded by reimaging with another lens such as at 6. The flare control which is introduced in this system is why a mirror or beam splitter is no longer required to control the contrast of the mask produced at 1 by imaging the recorded image at 2. 
     The image at 2 can be recorded on a transparent photo sensitive material when the image at 1 is illuminated by light 3 and allowed to expose this photo sensitive material. 
     One way of insuring registration of the recorded image formed at 2 with the original image at 1 is to not move the photo sensitive material after exposure at 2. This requires &#34;in situ&#34; development. One method of &#34;in situ&#34; development is discussed in U.S. Pat. Nos. 3,085,469 and 3,185,026 which utilizes, and is developed by radiant energy of a frequency different from the frequency at which it was exposed. 
     Another method of &#34;in situ&#34; development is illustrated in FIGS. 2, 3 and 4, which utilizes a film holder similar to the one described in my invention U.S. Pat. No. 4,422,753 with the addition of a developer applicator. This &#34;in situ&#34; development film holder is used at 2 FIG. 1. In FIGS. 2, 3 and 4 the light sensitive material 10 is placed in holder 11 and inserted into the focal position through slot 12. Before inserting the holder in slot 12 a monobath developer in a viscose form is placed along one edge of the sensitized material at 13, in FIG. 2. The dark slide 14 is removed, the material exposed (by means of light 3 FIG. 1). The dark slide 14, is inserted and applicator 15 either a brush, sponge, or doctor blade spreads the monobath over the photo material when pushed or pulled. Development and fixation take place in this dark box like film holder. Upon completion of development both dark slides 14 and 16 are removed and the exposed and processed transparency is ready for use as a mask. It is projected in register with the original at 1 FIG. 1 when illuminated by light source 17 in FIG. 1. 
     Light source 17, in FIG. 1, represents a well known color controlled dichroic lamp house. 
     Other more unconventional photo processes can be used with &#34;in situ&#34; development. Heat processes such as Kalvar or 3M dry silver can be processed by substituting a heated roller for the applicator 15 or using heater elements or hot air through a tube 18 in the film holder FIG. 2. Pressure processed materials such as those using incapsulated developers can be processed by using a pressure roller instead of applicator 15. Gas processed material such as Diazo can be processed by inserting gas into the film holder through a tube such as 18 FIG. 2. 
     Optical flare or vieling glare can be introduced into the system to lower the contrast of the projected image of 2 at 1 in a number of ways. One way is by means of a light diffusing filter inserted in the optical system anywhere between 1 and 2. A series of filters of different degrees of diffusion could control the degree of flare. 
     FIG. 5 illustrates an alternate method of producing a controlled amount of optical flare in the image forming optical system of FIG. 1. At the aperture stop of the lense 4 such as where an iris diaphragm is usually situated in a photo type lens, approximately at position 9 FIG. 1 a device like a &#34;Water House Stop&#34; FIG. 5 is inserted. This flare control device is an opaque insert 42 (See FIGS. 1 and 5) and contains an aperature 19 corresponding in size to the maximum diameter of the aperture in lens 4 FIG. 1. Covering this aperature is a difuse translucent (light scattering) material 20 with a smaller aperature 21 in it. This insert 42 when inserted in lens 4 FIG. 1 will scatter the light through lens 4 in proportion to the area of the light scattering diffuser 20 exposed at the aperature. The size of the hole can be varied with different inserts and thus control the amount of scatter and thereby control the flare or vieling glare in the optical system of FIG. 1. 
     FIG. 6 illustrates two continuously variable means for adjusting the amount of vieling glare or flare introduced into the optical system at 4 FIG. 1. One method is to utilize an iris diaphragm constructed of translucent light scattering material 22. The amount of diffusing material exposed at the aperature 23 determines the degree of scattering. No scattering is introduced into the optical system when the leaves are opened all the way and covered by aperature plate 24. The translucent iris is controlled by lever 25. 
     Instead of a translucent variable diaphragm as shown in FIG. 6 controlled means of flare can be introduced, at 42 FIG. 1 and FIG. 6 by means of a series of holes 26 around the aperature 23. These holes are covered with a translucent light scattering material and lie within the optical path but outside the region of best optical correction. A control lever 25 controls a sliding cover for these holes. Thus the degree of flare introduced into the optical systems is controlled. This method is similar to the way in which aberrations are introduced in controlled amounts to produce the well known variable soft focus lens. Other means of flare control will be obvious to one skilled in the art. 
     FIG. 7 represents alternate methods of accomplishing some of the same functions as shown in FIGS. 1 through 6. As in FIG. 1 the original at 1 is imaged on a light sensitive material at 2 when illuminated by light source 3. This image at 2 could be developed &#34;in situ&#34; as in FIGS. 1 and 2 or the light sensitive material could be removed and processed elsewhere. In the latter case a registration device such as registration pins 27 or a 3-way slide, with one rotational movement 28 and two orthoginal movements 29 in a plane perpendicular to the rotational axis, would be required to reposition the image of the processed mask in register with the original at 1 when illuminated by light source 30. It is also possible that the optical system used to produce the mask at 2 need not be the same system as used to image the mask in register with the original at 1. This can be accomplished by providing a method or methods of controlling the image size with elements #7 as in FIG. 1 or adjustments of the position of 2 as indicated by 31. These position adjustments can also control the degree of sharpness for unsharp masking as well as magnification. A diffusion screen or ground glass 32 can be used for receiving the image of 2 at 1 instead of using a field lens to even the illumination for reimaging by lens 33 at 34. Flare control or its equivalent can be accomplished by separately illuminating this screen 32 with controllable light 35, controlled by 36 or other techniques known to one experienced in the art. 
     Filter 37 FIG. 7 which can be placed anywhere in the system can be used to control the color of the light used for exposing the mask or the color of the light used to produce the final image at 34. One possible place for utilizing a color filter would be at the aperature of lens 4 FIG. 7. In this case a variable filter such as discussed in U.S. Pat. Nos. 2,234,108, 2,354,108 and 3,912,361 could be used. 
     Other ways of producing single channel flare controlled, sharpness controlled, image registration, photo projection systems will be obvious to one skilled in the art. The following are means which can be combined in various ways to produce the desired effect. 
     (a) Imaging means--lens conventional or catadioptric. 
     (b) Contrast or flare control means--filters, diffuse screen at aperture stop, additional light source, variable duffuse aperature, peripheral diffuse aperatures, etc. 
     (c) Sharpness control means--filters, glass plates, lens focus change 
     (d) Color control means--filters, dichroic lamphouse, additive color lamphouse 
     (e) Registration means--registration pins, in-situ development, registration sliders 
     (f) Means for recording combined image--contact recording, enlarging for prints or transparencies, transparency duplication, optical printer for cinephotography, etc. 
     (g) In-Situ development means--monobath applicator for conventional film, heat roller for thermal materials such as 3M or Kalvar, amonia cell for Diazo type material, pressure roller for encapsulated processes, charge powder applicator for electrostatic processes, light energy for photochromic processes, etc.