Abstract:
An optical image capturing module and an alignment method and an observation method for an upper substrate and a lower substrate using the optical image capturing module are provided. The upper substrate and the lower substrate are disposed opposite. The alignment method includes the following steps of: emitting a light ray; filtering the light ray and dividing the light ray into a light ray at first wavelength and a light ray at second wavelength, whereby the light ray at first wavelength irradiates a pattern on the upper substrate, and the light ray at second wavelength irradiates a pattern on the lower substrate; reflecting the pattern on the upper substrate to an image capturing device; reflecting the pattern on the lower substrate to the image capturing device; and determining the positions of the pattern on the upper substrate and the pattern on the lower substrate on the image capturing device.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of Taiwan Patent Application No. 101150499, filed on Dec. 27, 2012, which is hereby incorporated by reference for all purposes as if fully set forth herein. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of Invention 
         [0003]    The present invention relates to an optical image capturing module, and more particularly to an optical image capturing module formed by four prisms, two wavelength-selective films to filter the specific light ray with different wavelengths, an alignment method for an upper substrate and a lower substrate, and an observation method for an upper substrate and a lower substrate using the optical image capturing module of the present invention. 
         [0004]    2. Related Art 
         [0005]    U.S. Pat. No. 3,684,384 discloses a compound optical prism module, which is formed with a truncated quadrangular, right prism with a 45° truncation and a rectangular prism united to the optical prism module to form a parallelepiped with a half-silvered mirror film at their interface and with a total reflecting mirror film at the vertical surface of the rectangular prism, so that the two components are opposed in their mated positions can be superposed in the same coordinate space for image observation. However, this prior art patent discloses the use of two right-angle prisms with different sizes, resulting in different lengths for an upper light path length and a lower light path length, limited manners of mounting light sources, and also a large module volume. 
         [0006]    U.S. Pat. No. 5,519,535 also discloses a compound optical prism module, which is formed with two same size right-angle prisms and similar to U.S. Pat. No. 3,684,384. More particularly, a liquid crystal shutter is mounted onto one face of each right-angle prisms control image showing for objects at different sides, respectively. However, the liquid crystal shutter disclosed in this prior art patent sacrifices light intensity efficiency to some degree, and a number of control components are required. 
         [0007]    U.S. Pat. No. 4,574,197 discloses a dual field of view sensing device, in which mainly a polygonal prism is used, and through mechanism rotation control, a light ray is refracted and then two parallel light paths are reflected into a single detector to obtain symmetrical light paths; switching of the light paths depends on the rotational position of the prism, and two different light beams are reflected into a single image space through the prism. However, the device volume disclosed in this prior art patent is too large, the light path is designed too long, and the mechanical control is too complicated. 
         [0008]    In the prior art, to map two different images (or light beams) in a single image plane, different prism forms are mainly adopted, and the aforementioned prior art patents (U.S. Pat. No. 3,684,384 and U.S. Pat. No. 5,519,535) are the most common, in which a compound prism is used to reflect light paths from opposite image positions into a single image space. However, the problem that the reflection path lengths of the opposite light rays are not equal occurs in both patents. By taking image capturing into consideration, the working distance become unequal, causing that the opposite side objects must be placed at asymmetrical distances, which makes the fabrication process complicated. Also, currently a compound prism module has a number of refraction paths and a large volume, and no longer satisfied the current fabrication processes in the optoelectronics industry. 
         [0009]    Therefore, an optical image capturing module having symmetrical light paths needs to be provided to solve the foregoing problem. 
       SUMMARY OF THE INVENTION 
       [0010]    The purpose of the present invention is to provide an optical image capturing module having symmetrical light path lengths and helpfully reducing a component volume of an image module, an alignment method, and an observation method for an upper substrate and a lower substrate applying the optical image capturing module. 
         [0011]    To achieve the above objectives, the present invention provides an optical image capturing module including: an image capturing device; a first prism, having a first face, a second face, and a third face, wherein the first face and the second face of the first prism have an equal sectional length; a second prism, having a first face and a second face, wherein the first face and the second face of the second prism have an equal sectional length, and the second face of the second prism is adjacent to the first face of the first prism; a third prism, having a first face and a second face, wherein the first face and the second face of the third prism have an equal sectional length, and the first face of the third prism is adjacent to the second face of the first prism; a fourth prism, having a first face and a second face, wherein the first face and the second face of the fourth prism have an equal sectional length, the first face of the third prism is adjacent to the second face of the third prism, and the second face of the fourth prism is adjacent to the first face of the second prism; a beam splitter, disposed between the first prism and the image capturing device, and located at a side of the third face of the first prism; a light source, used to emit a light ray, wherein the light ray enters the beam splitter, and a direction that the light ray enters the beam splitter is perpendicular to an image receiving direction of the image capturing device; a first wavelength-selective film with a selective wavelength higher than a cut-off wavelength, wherein a part of the first wavelength-selective film is located between the first face of the first prism and the second face of the second prism, and another part of the first wavelength-selective film is located between the second face of the third prism and the first face of the fourth prism, the first wavelength-selective film allows a first wavelength light ray at the wavelengths higher than a cut-off wavelength to pass through, and reflects a second wavelength light ray at the wavelengths lower than the cut-off wavelength; and a second wavelength-selective film with a selective wavelength lower than the cut-off wavelength, wherein a part of the second wavelength-selective film is located between the second face of the first prism and the first face of the third prism, and another part of the second wavelength-selective film is located between the first face of the second prism and the second face of the fourth prism, the second wavelength-selective film allows the second wavelength light ray at the wavelengths lower than the cut-off wavelength to pass through and reflects the first wavelength light ray at the wavelengths higher than the cut-off wavelength. 
         [0012]    The present invention further provides an alignment method for an upper substrate and a lower substrate, the upper substrate and the lower substrate being disposed opposite, and the alignment method including the following steps of: emitting a light ray; filtering the light ray to divide the light ray into a first wavelength light ray and a second wavelength light ray, whereby the first wavelength light ray irradiates a pattern on the upper substrate, and the second wavelength light ray irradiates a pattern on the lower substrate; reflecting the pattern on the upper substrate to an image capturing device; reflecting the pattern on the lower substrate to the image capturing device; and determining the positions of the pattern on the upper substrate and the pattern on the lower substrate on the image capturing device. 
         [0013]    The present invention further provides an observation method, used to observe a pattern on an upper substrate or a lower substrate, the upper substrate and the lower substrate being disposed opposite, and the observation method including the following steps of: emitting a first wavelength light ray, and irradiating the upper substrate; reflecting the pattern on the upper substrate to an image capturing device; observing the pattern on the upper substrate; turning off the first wavelength light ray; emitting a second wavelength light ray, and irradiating the lower substrate; reflecting the pattern on the lower substrate to the image capturing device; and observing the pattern on the lower substrate. 
         [0014]    The present invention can provide symmetrical light path lengths, helpfully reduce the volume of an image module component, and can achieve symmetrically working distances, and symmetry is achieved for the images at the two sides. Compared with that a compound right-angle prism causes unequal reflection path lengths for the light rays from the upper object and the lower object in the prior art, considering in terms of image capturing, the present invention does not cause unequal working distances, and therefore the upper object and the lower object (an upper substrate and a lower substrate) in the present invention are not required to be placed at symmetrical distances. 
         [0015]    To make the aforementioned and other objects, features and advantages of the present invention clearer, detailed illustration is provided in the following with reference to the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0016]    The present invention will become more fully understood from the detailed description given herein below for illustration only, and thus are not limitative of the present invention, and wherein: 
           [0017]      FIG. 1   a  is a schematic structural view of an optical image capturing module according to an embodiment of the present invention; 
           [0018]      FIG. 1   b  is a schematic structural view of an optical image capturing module according to an embodiment of the present invention showing a light path of a first wavelength light ray at the wavelength higher than the cut-off wavelength; 
           [0019]      FIG. 1   c  is a schematic structural view of an optical image capturing module according to an embodiment of the present invention showing a light path of a second wavelength light ray at the wavelengths lower than the cut-off wavelength; 
           [0020]      FIG. 1   d  is a spectral diagram for showing different light wavelengths of a first wavelength-selective film and a second wavelength-selective film; 
           [0021]      FIG. 2  is a flow chart of an alignment method according to an embodiment of the present invention; 
           [0022]      FIG. 3   a  is a schematic sectional view of an upper substrate, a lower substrate, and an optical image capturing module. 
           [0023]      FIG. 3   b  is a plane view of an upper substrate; 
           [0024]      FIG. 3   c  is a plane view of a lower substrate; 
           [0025]      FIG. 3   d  is a schematic view showing the pattern on an upper substrate overlaps the pattern on a lower substrate; and 
           [0026]      FIG. 4  is a flow chart of an observation method according to an embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0027]    Please refer to  FIG. 1   a .  FIG. 1   a  is a schematic structural view of an optical image capturing module according to an embodiment of the present invention. An optical image capturing module  100  includes: an image capturing device  180 , a first prism  110 , a second prism  120 , a third prism  130 , a fourth prism  140 , a first wavelength-selective film  150 , a second wavelength-selective film  160 , a beam splitter  170 , and a light source  190 . The first prism  110 , the second prism  120 , the third prism  130 , and the fourth prism  140  all have a first face, a second face and a third face, and the first face and the second face have an equal sectional length, for example, a first face  111  and a second face  112  of the first prism  110  have an equal sectional length. 
         [0028]    A part of the first-selective film  150  is formed on the first face  111  of the first prism  110  or a second face  122  of the second prism  120 , and another part of the first wavelength-selective film  150  is formed on a second face  132  of the third prism  130  or a first face  141  of the fourth prism  140 . A part of the second wavelength-selective film  160  is formed on the second face  112  of the first prism  110  or a first face  131  of the third prism  130 , and another part of the second wavelength-selective film  160  is formed on a first face  121  of the second prism  120  or a second face  142  of the fourth prism  140 . In this embodiment, a part of the first wavelength-selective film  150  is formed on the first face  111  of the first prism  110 , another part of the first wavelength-selective film  150  is formed on the first face  141  of the fourth prism  140 , a part of the second wavelength-selective film  160  is formed on the second face  112  of the first prism  110 , and another part of the second wavelength-selective film  160  is formed on the second face  142  of the fourth prism  140 . The first wavelength-selective film  150  and the second wavelength-selective film  160  are transmissive for a light ray at specific wavelengths and reflect light rays of other wavelengths, and the specific wavelengths may be a single wavelength or wavelengths in a range. Please refer to  FIG. 1   d  at the same time.  FIG. 1   d  is a spectral diagram for showing different light wavelengths of a first wavelength-selective film and a second wavelength-selective film. In  FIG. 1   d , the horizontal axis represents wavelengths, the vertical axis represents that the first and second-selective films have different transmittances for describing transmissive capacity and light intensity with wavelengths, the curve  150   a  represents a transmittance curve of the first wavelength-selective film  150 , the curve  160   a  represents a transmittance curve of the second wavelength-selective film  160 , the intersection between the curve  150   a  and the curve  160   a  is a cut-off wavelength as the position shown by the dotted line  194  in  FIG. 1   d . In this embodiment, the designed cut-off wavelength is 550 (nm), so that the first wavelength-selective film  150  allows the light ray at the wavelength [for example, 635 (nm)] higher than the cut-off wavelength to pass through and reflects the light ray at the first wavelength [for example, 445 (nm)] lower than the cut-off wavelength. The second wavelength-selective film  160  allows the light ray at the second wavelength [for example, 445 (nm)] lower than the cut-off wavelength to pass through and reflects the light ray at the first wavelength [for example, 635 (nm)] higher than the cut-off wavelength. The first wavelength is higher than the cut-off wavelength, and the second wavelength is lower than the cut-off wavelength. 
         [0029]    The second face  122  of the second prism  120  is adjacent to the first face  111  of the first prism  110 , so that a part of the first wavelength-selective film  150  is located between the first face  111  of the first prism  110  and the second face  122  of the second prism  120 . The first face  131  of the third prism  130  is adjacent to the second face  112  of the first prism  110 , so that a part of the second wavelength-selective film  160  is located between the second face  112  of the first prism  110  and the first face  131  of the third prism  130 . 
         [0030]    The first face  141  of the fourth prism  140  is adjacent to the second face  132  of the third prism  130 , so that another part of the first wavelength-selective film  150  is located between the second face  132  of the third prism  130  and the first face  141  of the fourth prism  140 . The second face  142  of the fourth prism  140  is adjacent to the first face  121  of the second prism  120 , so that another part of the second wavelength-selective film  160  is located between the first face  121  of the second prism  120  and the second face  142  of the fourth prism  140 . 
         [0031]    The beam splitter  170  is disposed between the first prism  110  and the image capturing device  180 , and is located at a side of a third face  113  of the first prism  110 . 
         [0032]    The light source  190  is used to emit a light ray  191 , the light ray  191  enters the beam splitter  170 , and the direction that the light ray  191  enters the beam splitter  170  is perpendicular to an image receiving direction of the image capturing device  180 . The light source  190  may have a switching function and is capable of emitting a first wavelength light ray  192  (i.e., the light ray with first wavelength)  192  or a second wavelength light ray  193  (i.e., the light ray with second wavelength), or the light source  190  is also capable of emitting white light. In this implementation, the first wavelength light ray  192  refers to a light ray at a single wavelength [for example, 635 (nm)] higher than a cut-off wavelength 550 (nm), and the second wavelength light ray  193  refers to a light ray at a single wavelength [for example, 445 (nm)] lower than the cut-off wavelength 550 (nm). However, the first wavelength light ray or the second wavelength is not limited at the single wavelengths, and may also be a light ray at a continuous wavelength range, for example: the first wavelength light ray  192  is a light ray higher than the cut-off wavelength 550 (nm), and the range of the light wavelength is 550 (nm) to 700 (nm). The second wavelength light ray  193  is a light ray lower than 550 (nm), and the range of the light wavelength is 400 (nm) to 550 (nm). Please refer to  FIG. 1   b , it is assumed that when the light source  190  emits the first wavelength light ray  192 , being partially reflected by the beam splitter  170 , the light ray enters through the third face  113  of the first prism  110 , at this time, the path of the first wavelength light ray  192  is the following two: 
         [0033]    The first path is that: the first wavelength light ray  192  reaches the first face  111  of the first prism  110 , the first wavelength light ray  192  is directly transmitted to the second prism  120  because of the first wavelength-selective film  150 , and as the second wavelength-selective film  160  is formed on the second face  142  of the fourth prism  140 , the first wavelength light ray  192  is reflected by the second wavelength-selective film  160  and is emitted from a third face  123  of the second prism  120 . 
         [0034]    The second path is: the first wavelength light ray  192  reaches the second face  112  of the first prism  110 , and the first wavelength light ray  192  is reflected and passes through the first face  111  of the first prism  110 , the second face  122  of the second prism  120 , and the third face  123  of the second prism  120  sequentially because of the second wavelength-selective film  160 . 
         [0035]    If the first wavelength light ray  192  leaves the third face  123  of the second prism  120  and reaches an upper substrate  910  and is reflected, the reflected light ray moves reversely along the aforementioned first or second path, and is partially transmitted through the beam splitter  170 , so as to form an image on the image capturing device  180 , so that the image capturing device  180  can photograph the pattern on the upper substrate  910 . 
         [0036]    Please refer to  FIG. 1   c . It is assumed that when the light source  190  emits the second wavelength light ray  193 , being reflected by the beam splitter  170 , the second wavelength light ray  193  enters from the third face  113  of the first prism  110 , and at this time, the path of the second wavelength light ray  193  is the following two: 
         [0037]    The first path is that: the second wavelength light ray  193  reaches the first face  111  of the first prism  110 , because of the first wavelength-selective film  150 , the second wavelength light ray  193  is reflected and passes through the second face  112  of the first prism  110 , the first face  131  of the third prism  130 , and a third face  133  of the third prism  130 . 
         [0038]    The second path is that: the second wavelength light ray  193  reaches the second face  112  of the first prism  110 , the second wavelength light ray  193  is directly transmitted to the third prism  130  because of the second wavelength-selective film  160 , and as the first wavelength-selective film  150  is formed on the first face  141  of the fourth prism  140 , the second wavelength light ray  193  is reflected by the first wavelength-selective film  150  and emits from the third face  133  of the third prism  130 . 
         [0039]    If the light ray leaves the third face  133  of the third prism  130  and reaches a lower substrate  920  and is reflected, the reflected light ray moves reversely along the aforementioned first or second path, and is partially transmitted through the beam splitter  170 , so as to form an image on the image capturing device  180 , so that the image capturing device  180  can photograph the pattern on the lower substrate  920 . 
         [0040]    If the light source  190  emits white light, the white light is divided into the first wavelength light ray  192  and the second wavelength light ray  193  because of the design of the first wavelength-selective film  150  and the second wavelength-selective film  160 . The first wavelength light ray  192  moves along the path of the first wavelength light ray  192  shown in  FIG. 1   b , and the second wavelength light ray  193  moves along the path of the second wavelength light ray  193  shown in  FIG. 1   c , and light rays reaching the upper substrate and the lower substrate form images on the image capturing device  180  at the same time, so that the image capturing device  180  can observe the patterns on the upper substrate and the lower substrate at the same time. 
         [0041]      FIG. 2  is a flow chart of an alignment method according to an embodiment of the present invention. The alignment method is mainly used for aligning an upper substrate and a lower substrate.  FIG. 3   a  is a schematic sectional view of an upper substrate, a lower substrate, and an optical image capturing module and shows the relative positions. The upper substrate  910  and the lower substrate  920  are disposed opposite, and two groups of optical image capturing modules  100  are disposed between the upper substrate  910  and the lower substrate  920 . The alignment method mainly adopts the optical image capturing module  100  in the embodiment of the present invention, and the optical image capturing module  100  is disposed between the upper substrate  910  and the lower substrate  920 .  FIG. 3   b  is a plane view of an upper substrate and shows an X-shaped pattern  911  on the surface of the upper substrate  910 .  FIG. 3   c  is a plane view of a lower substrate and shows an O-shaped pattern  921  on the surface of the lower substrate  920 . Please refer to  FIG. 1   a  to  FIG. 1   c ,  FIG. 2 , and  FIG. 3   a  to  FIG. 3   d  at the same time. 
         [0042]    Step S 100 : Emit a light ray. In this step, a light source  190  emits a light ray, and the light ray is white light or a light ray having a first wavelength light ray  192  and a second wavelength light ray  193  at the same time. 
         [0043]    Step S 102 : Filter the light ray to divide the light ray into a first wavelength light ray and a second wavelength light ray, the first wavelength light ray irradiating the pattern on the upper substrate, and the second wavelength light ray irradiating the pattern on the lower substrate. In this step, the paths of the first and second wavelength light ray  192 ,  193  are shown in  FIG. 1   b  and  FIG. 1   c . Therefore, the first wavelength light ray  192  irradiates the X-shaped pattern  911  on the upper substrate  910  (shown in  FIG. 3   b ), and the second wavelength light ray  193  irradiates the O-shaped pattern  921  on the lower substrate  920  (shown in  FIG. 3   c ). 
         [0044]    Step S 104 : Reflect the pattern on the upper substrate to an image capturing device. In this step, the first wavelength light ray  192  irradiates the X-shaped pattern  911  on the upper substrate  910  and is reflected, and the reflected first wavelength light ray  192  irradiates the image capturing device  180  along the original light path. Therefore, the X-shaped pattern  911  on the upper substrate  910  forms an image on the image capturing device  180 . 
         [0045]    Step S 106 : Reflect the pattern on the lower substrate to the image capturing device. In this step, the second wavelength light ray  193  irradiates the O-shaped pattern  921  on the lower substrate  920  and is reflected, and the reflected second wavelength light ray  193  irradiates the image capturing device  180  along the original light path. Therefore, the O-shaped pattern  921  on the lower substrate  920  forms an image on the image capturing device  180 . 
         [0046]    Step S 104  and Step S 106  take place at the same time. Therefore, the X-shaped pattern  911  on the upper substrate  910  and the O-shaped pattern  921  on the lower substrate  920  form images on the image capturing device  180 . 
         [0047]    Step S 108 : Determine the positions of the pattern on the upper substrate and the pattern on the lower substrate on the image capturing device. In this step, as the X-shaped pattern  911  on the upper substrate  910  and the O-shaped pattern  921  on the lower substrate  920  form images on the image capturing device  180  at the same time, the positions of the pattern on the upper substrate  910  and the pattern on the lower substrate  920  on the image capturing device  180  can be learned in an image determination manner. 
         [0048]    Step S 110 : Move the upper substrate or the lower substrate to make the pattern on the upper substrate and the pattern on the lower substrate overlap each other on the image capturing device. In this step, the upper substrate  910  or the lower substrate  920  is moved horizontally, and when the X-shaped pattern  911  on the upper substrate  910  and the O-shaped pattern  921  on the lower substrate  920  overlap each other on the image capturing device  180  (shown in  FIG. 3   d ), it can be determined that the alignment action has been accomplished for the upper substrate  910  and the lower substrate  920 . 
         [0049]      FIG. 4  is a flow chart of an observation method according to an embodiment of the present invention. The observation method can be used to observe the surfaces of the upper substrate  910  or the lower substrate  920 . The observation method mainly adopts the optical image capturing module  100  in the embodiment of the present invention, and the optical image capturing module  100  is disposed between the upper substrate  910  and the lower substrate  920  (shown in  FIG. 3   a ). Please refer to  FIG. 1   a  to  FIG. 1   c ,  FIG. 3   a  to  FIG. 3   c , and  FIG. 4  at the same time. 
         [0050]    Step S 200 : Emit a first wavelength light ray, and irradiate an upper substrate. In this step, a light source  190  emits a light ray at first wavelength  192 . The path of the first emitted light ray  192  is shown in  FIG. 1   b . Therefore, the first emitted light ray  192  irradiates the X-shaped pattern  911  on the upper substrate  910  (shown in  FIG. 3   b ). 
         [0051]    Step S 202 : Reflect the pattern on the upper substrate to an image capturing device. In this step, the first emitted light ray  192  irradiates the X-shaped pattern  911  on the upper substrate  910  and is reflected, and the reflected first emitted light ray  192  irradiates the image capturing device  180  along the original light path. Therefore, the X-shaped pattern  911  on the upper substrate  910  forms an image on the image capturing device  180 . 
         [0052]    Step S 204 : Observe the pattern on the upper substrate. In this step, the image capturing device  180  observes the X-shaped pattern  911  on the upper substrate  910 . 
         [0053]    Step S 206 : Turn off the first emitted light ray. In this step, the light source  190  is controlled to stop the light source  190  from emitting the first emitted light ray  192 . 
         [0054]    Step S 208 : Emit a second wavelength light ray, and irradiate a lower substrate. In this step, the light source  190  emits a second wavelength light ray  193 , the path of the second wavelength light ray  193  shown in  FIG. 1   c , and the second wavelength light ray  193  irradiates the O-shaped pattern  921  on the lower substrate  920  (shown in  FIG. 3   c ). 
         [0055]    Step S 210 : Reflect the pattern on the lower substrate to the image capturing device. In this step, the second wavelength light ray  193  irradiates the O-shaped pattern  921  on the lower substrate  920  and is reflected, and the reflected second wavelength light ray  193  irradiates the image capturing device  180  along the original light path. Therefore, the O-shaped pattern  921  on the lower substrate  920  forms an image on the image capturing device  180 . 
         [0056]    Step S 212 : Observe the pattern on the lower substrate. In this step, the image capturing device  180  observes the O-shaped pattern  921  on the lower substrate  920 . 
         [0057]    In conclusion, the present invention has the following characteristics: 
         [0058]    1. The present invention can provide symmetrical light path lengths, helpfully reduce the volume of an image module component, and can achieve symmetrically working distances, and symmetry is achieved for the images at the two sides. Compared with that a compound right-angle prism causes unequal reflection paths for the light rays from the upper object and the lower object in the prior art, considering in terms of image capturing, the present invention does not cause unequal working distances, and therefore the upper object and the lower object (an upper substrate and a lower substrate) in the present invention are not required to be placed at symmetrical distances. 
         [0059]    2. The present invention can provide an imaging method capable of irradiating objects to test by adopting light paths of coaxial light sources. Compared with an imaging method that a compound right-angle prism only can only irradiate objects to test by using external light sources in the prior art, the flexibility and applications for spatial use are further enhanced. 
         [0060]    3. The present invention can provide a mechanism of rapidly switching light paths, physical shutter components are not required, and compared with a conventional mechanical or electronic liquid crystal shutter, the time is shorter and the control manner is simpler. 
         [0061]    4. The present invention can effectively increase alignment precision for the alignment of an upper substrate and a lower substrate and reduce errors resulting from optical and mechanical component assembly. 
         [0062]    5. The present invention is applicable to industries requiring precise alignment and positioning, such as touch panel and IC electronic bonding, provides a high-stability image display manner, reduces errors and labeling problems in mechanical movement control, and enhances the fabrication process technologies, production speed, and product yield in the industries. 
         [0063]    The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.