JP2006038810A - Device and method for measuring performance of optical system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high precision device and a method for measuring the characteristics of an optical system for use in a projection lens or an imaging lens. <P>SOLUTION: In the device and the method for performing the magnification projection of a target (slit), disposed on the focal plane of the optical system to be measured by an illumination means and for measuring the performance, by receiving the intensity distribution of the projected image by a light receiving means disposed at a mechanism capable of performing the longitudinal and lateral scanning in a plain at the evaluation distance; the light receiving means can be rotated in a vertical plane about a horizontal normal axis, receives the light output distribution of the target image according to the measurement purpose, in a state in which it is inclined to the emission pupil direction of the optical system to be measured, and measures the performance of the optical system, by performing the correction according to the inclination angle and the processing according to the measurement purpose by a calculation means. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  In the present invention, the performance of an optical system used as a projection lens or a photographing lens, specifically, an MTF (Modulation Transfer Function), a target (slit) image is enlarged and projected onto a light receiving means, and the optical system is output from the light receiving means output. The present invention relates to an optical system performance measuring apparatus and method for measuring and evaluating the above.

  FIG. 7 shows a configuration example of a conventional optical performance measuring device for a photographic lens and a projection lens. In the example of measuring a coaxial lens, a slit image is formed on a CCD surface arranged in a line shape, and the intensity distribution is obtained. MTF is required.

  Reference numeral 70 denotes an optical system to be measured, and reference numeral 71 denotes a light source unit which includes a lamp and a condenser lens. Reference numeral 72 denotes a target (chart) portion, in which slits having a width corresponding to the measurement purpose are engraved for each measurement angle of view, and the distance between the optical system 70 to be measured and the target 72 can be adjusted. A light receiving unit 73 is arranged at a predetermined distance and can scan the evaluation surface. For example, the light receiving unit 73 is set as 73a and is used for measuring the off-axis MTF. The light receiving means 73 incorporates a CCD line sensor (not shown). In addition, it is composed of a moving means of the light receiving means 73 (not shown), an arithmetic processing means and the like.

  The measurement is performed as follows. The slit of the target 72 illuminated by the light source unit 71 is enlarged and projected by the measured optical system, and an output from the line sensor in which the projected image intensity distribution is incorporated in the light receiving means 73 is obtained. The intensity distribution of the slit image is called LSF (Lin Spread Function), and the output form is as shown in FIG. For LSF, the MTF is obtained by the calculation means in consideration of the slit and the projection magnification. In general, Fourier transform is performed on discrete frequencies, and the MTF for each frequency is obtained based on the ratio to the ideal Fourier image obtained from the slit width.

The above description is on the optical axis, and for off-axis measurement, the light receiving means 73 is moved within the measurement plane to set the target angle θ1 position 73a, and the measurement value is obtained in the same manner as on the axis.
JP 2001-255462 A JP 2000-89227 A

  In the conventional optical system performance measuring apparatus and method described above, there is no problem when the light receiving element is set at an angle close to perpendicular to the optical axis of the lens to be measured, but at the position of the light receiving means 73a shown in FIG. When the angle θ1 is further increased, the intensity distribution of the slit image, that is, the LSF is more accurate than the case of normal incidence due to characteristics that affect the intensity distribution such as sensor sensitivity reduction, crosstalk, smear, and increased reflected light of the cover glass. Will not be measured.

  In addition to conventional wide-angle photographing lenses, in particular, thin rear projector devices and front projectors equipped with large wide-angle lenses have recently become widespread, and the projection angle from the optical axis has increased over 60 degrees.

  FIG. 9 shows how the intensity distribution of the projection image changes by connecting the slit image on the line sensor and changing the tilt angle of the light receiving means 73 in FIG. In FIG. 9, the attached numbers indicate the inclination angle of the oblique incidence with respect to the normal incidence to the light receiving means, and the projected image is measured differently from the shape of the normal incidence when the angle is increased. The value is also inaccurate.

  Also, in the MTF evaluation, the color temperature setting, that is, the intensity distribution for each wavelength of the light source and the light receiving element must be matched with the sunlight spectrum distribution and the spectral sensitivity of the film or CCD if it is daytime with the taking lens, for example. There is. However, since it was technically difficult to achieve this, it was limited to measurement evaluation based on the illumination system spectral distribution used for measurement, and it was sometimes different from the actual performance.

  Further, in the MTF measurement, the optical system optical axis to be measured and the projection evaluation surface must be set perpendicular to each other, and the target surface and the projection evaluation surface must be set in parallel. If the optical axis of the optical system to be measured is perpendicular to the projection evaluation surface, and the parallelism between the target surface and the projection evaluation surface is broken, even if the performance is normal, the measurement value is asymmetrical as if manufacturing and assembly errors have increased. It will be measured as a so-called single blur. In recent years, an off-axis optical system using a free-form surface is an optical system in which the perpendicular direction between the central axis of the optical system and the center of the projection screen does not match, and is used for a projector lens or the like. For example, those disclosed in Patent Documents 1 and 2 are disclosed. In the optical system as described above, a method used in the conventional MTF measurement method, for example, a slit image from the target surface is formed on the light receiving means, and the slit image reflected by the reflecting mirror disposed on the surface is covered. If it returns to the center of the measurement optical system, a method that the optical axis of the measurement optical system is perpendicular to the projection evaluation surface cannot be taken.

  Furthermore, the evaluation (MTF measurement) of the resolving power and sharpness of the projected image including the optical performance in which the image created by the PC is displayed on a light modulation element such as an LCD relies on subjective evaluation, especially the absolute evaluation measurement with numerical values. The current situation is that no.

  In addition to the problems described above, there is a problem that the measurement takes time because the entire projection evaluation surface is scanned and measured.

  In order to solve the above-described problems, the present invention provides a mechanism in which a target placed on a focal plane of an optical system to be measured is enlarged and projected by an illuminating unit, and can be scanned vertically and horizontally within an evaluation distance plane. In the apparatus for receiving the projected image intensity distribution by the arranged light receiving means and measuring the performance, the light receiving means can rotate in the vertical plane and around the horizontal vertical axis, and the exit pupil of the optical system to be measured. Means for providing a state tilted in the direction, means for receiving the output distribution of the target image according to the measurement purpose, and means for performing correction according to the tilt angle by the arithmetic means and processing according to the measurement purpose are provided.

  The light-receiving element used in the light-receiving means has means for receiving light at a plurality of wavelengths having different wavelength ranges, and means for correcting according to the weight ratio with respect to the color of the light source for evaluation from each received light intensity And means for calculating the optical system performance after performing the white balance processing.

  In claim 3, the target arranged on the focal plane of the optical system to be measured is enlarged and projected by the illuminating means, and the projected image intensity distribution is received by the light receiving means arranged in a mechanism capable of scanning vertically and horizontally within the plane of the evaluation distance, In the apparatus for measuring performance, in order to match the parallelism between the evaluation projection surface and the target surface and the optical axis of the optical system to be measured, projection optical system means for adjusting the optical axis different from the optical system to be measured is provided. Have.

  According to a fourth aspect of the present invention, the projection optical system means for adjusting the optical axis is a means using a laser light source and a diffraction grating chart, and the symmetrical spread of the diffraction grating is deviated from the left and right or upper and lower centers on the projection evaluation plane. It has means for measuring the difference, and means for adjusting the whole projection system in order to eliminate the deviation amount.

  According to a fifth aspect of the present invention, the target arranged on the focal plane of the optical system to be measured is enlarged and projected by the illuminating means, and the projected image intensity distribution is received by the light receiving means arranged in a mechanism capable of scanning vertically and horizontally within the plane of the evaluation distance. In the apparatus for measuring the optical system, the optical system to be measured and the means for illuminating the target arranged on the focal plane have means configured integrally, a means for setting the distance between the projection evaluation surface and the target, and an up / down / left / right moving means And has usable means in horizontal and vertical planes.

  According to a sixth aspect of the present invention, the target arranged on the focal plane of the optical system to be measured is enlarged and projected by the illumination means, and the projected image intensity distribution is received by the light receiving means arranged in a mechanism capable of scanning vertically and horizontally within the plane of the evaluation distance. A device for creating and displaying a target image on a light modulation element such as an LCD with a PC, and a means for measuring and evaluating the optical performance of the projected image intensity distribution by the light receiving means and the arithmetic processing unit. ing.

  According to a seventh aspect of the present invention, the target placed on the focal plane of the optical system to be measured is enlarged and projected by the illuminating means, and the projected image intensity distribution is received by the light receiving means arranged in a mechanism capable of scanning vertically and horizontally within the plane of the evaluation distance. In the apparatus which measures this, it has a means provided with two or more said light-receiving means.

(Function)
According to the first aspect of the present invention, the target arranged on the focal plane of the optical system to be measured is enlarged and projected by the illuminating means, and the projected image intensity distribution is received by the light receiving means arranged in the mechanism capable of scanning vertically and horizontally within the plane of the evaluation distance. The light receiving means is a means capable of rotating in a vertical plane and around a horizontal vertical axis, a means for tilting in the exit pupil direction of the optical system under measurement, and a target image corresponding to the measurement purpose. Means for receiving the output distribution and means for performing correction according to the inclination angle by the arithmetic means and processing according to the measurement purpose are provided.

  Therefore, the light receiving means always reaches a target image that is directly opposed regardless of the projection angle of view, so that an accurate output distribution of the target image is obtained, and the spread of the slit image due to the inclination of the light receiving means is corrected by the calculating means. Therefore, an accurate measurement value can be obtained.

  According to a second aspect of the present invention, the light receiving element used in the light receiving means receives light at a plurality of wavelengths having different wavelength ranges, means for correcting according to the weight ratio with respect to the color of the light source to be evaluated from each received light intensity, and optical Since the system performance calculation means is provided, the measured value of the optical system in the illumination light source actually used can be obtained.

  According to another aspect of the present invention, the target image arranged on the focal plane of the optical system to be measured is enlarged and projected by the illuminating means, and the projected image intensity is obtained by the light receiving means arranged on the mechanism capable of scanning vertically and horizontally within the evaluation distance plane. In an apparatus for receiving the distribution and measuring the performance, in order to match the parallelism between the evaluation projection surface and the target surface and the optical axis of the optical system to be measured, the optical axis is different from that of the optical system to be measured. Since the projection optical system means is provided, the operation of matching the parallelism between the evaluation projection surface and the target surface and the optical axis of the optical system to be measured can be performed in the measurement of the off-axis optical system or the like.

  According to a fifth aspect of the present invention, the target arranged on the focal plane of the optical system to be measured is enlarged and projected by the illuminating means, and the projected image intensity distribution is received by the light receiving means arranged in a mechanism capable of scanning vertically and horizontally within the plane of the evaluation distance. In the apparatus for measuring the optical system, the means for illuminating the optical system to be measured and the target arranged on the focal plane has means configured integrally, a means for setting the distance between the projection evaluation surface and the target, and vertical and horizontal movement Since it is possible to easily adjust the verticality of the projection evaluation surface and the optical axis of the optical system to be measured, the projection image can be focused on the sensor of the light receiving means. And defocus characteristics can be measured. Furthermore, in the evaluation of a projection optical system or a shift optical system in which the position of the evaluation screen moves greatly, performance may not be able to be measured due to local restrictions when projecting a large shift vertically (vertically) or horizontally (horizontal). There is also a thing. For example, when the screen is moved up and down, if there is no margin and there is a margin on the left and right, it can be easily rotated 90 degrees, and it is not necessary to move a large and heavy scanning device. .

  According to a sixth aspect of the present invention, the target arranged on the focal plane of the optical system to be measured is enlarged and projected by the illumination means, and the projected image intensity distribution is received by the light receiving means arranged in a mechanism capable of scanning vertically and horizontally within the plane of the evaluation distance. A device for creating and displaying a target image on a light modulation element such as an LCD with a PC, and a means for measuring and evaluating the optical performance of the projected image intensity distribution by the light receiving means and the arithmetic processing unit. Therefore, in addition to being able to perform measurement under actual use conditions, it is possible to quantify measurement that relies on conventional subjective evaluation.

  According to a seventh aspect of the present invention, the target placed on the focal plane of the optical system to be measured is enlarged and projected by the illuminating means, and the projected image intensity distribution is received by the light receiving means arranged in a mechanism capable of scanning vertically and horizontally within the plane of the evaluation distance. In the apparatus for measuring the above-mentioned, since it has means including a plurality of light receiving means, the scanning range can be determined for each light receiving means and the measurement can be performed efficiently. Since point data is also obtained, detailed data of the optical system to be measured can be obtained.

  In the optical system performance measuring apparatus and method according to the present invention described above, when the projection angle or photographing angle from the optical axis is increased, measurement according to the illumination light source used, and optical axis alignment are accurately performed. Therefore, accurate performance measurement of the optical system to be tested can be performed efficiently.

  Further, since the performance of the projector optical system can be obtained as absolute numerical data in the usage state, the evaluation is accurately performed.

Example 1
Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing an outline of the overall configuration of an apparatus for measuring MTF for a front projector that uses an off-axis optical system in the first embodiment of the present invention and projects in an upwardly biased form. FIG. 2 is a schematic view when the light receiving means side is viewed from the test optical system side.

  The configuration is as follows. Reference numeral 10 denotes an optical system to be measured, 20 denotes a projection unit, a light source unit 21 including a lamp and a condenser, a tilt adjustment unit 22, a shift adjustment unit 23, a test object mounting unit 24, and a target (chart) unit 25 that can be replaced depending on the measurement purpose. The focus adjustment mechanism 26 is included. Reference numeral 30 denotes a PC (system control / arithmetic unit), 31 denotes a PC display unit, and 40 denotes a movable loading table. Reference numeral 50 denotes a scanning unit, in which three light receiving units 60 (60a, 60b, 60c) are arranged, and color line sensors 61 (61a, 61b, 61c) as light receiving elements are respectively incorporated therein. The scanning unit 50 is provided with a vertical movement guide 51 and a horizontal movement guide 52.

  The function of each component is as follows. The projection unit 20 can be rotated vertically and horizontally, and the tilt angle with respect to the scanning unit can be adjusted by the tilt adjustment unit 22 and the shift adjustment unit 23. In the target unit 25, a slit having a width corresponding to the measurement screen size is engraved for each measurement angle of view. Further, the distance between the target unit 25 and the optical system 10 to be measured can be adjusted, and can be adjusted by the control of a PC (system control / arithmetic unit) 30 via the focus adjustment mechanism 26.

  Further, FIG. 3 is a view of the projection unit 20 shown in FIG. 1 as viewed from above, in which the laser light source illumination system 27 is inserted after the light source unit 21 is removed. When not in use, it will slide back into the storage. Reference numeral 29 is fixed by a laser light source.

  A detachable target is inserted into the target (chart) portion 25 shown in FIG. 1, but a diffraction grating 28 is attached to the optical axis alignment operation.

  The movable loading table 40 is movable up and down with the projection unit 20 loaded, and loads the PC 30 and the like. Furthermore, the distance between the measured optical system 10 and the scanning unit 50 can be set.

  The specification of the color line sensor 61, which is a light receiving element incorporated in the front surface of the light receiving unit 60, is a type in which three line sensors in which 4096 pixels of 7 × 10 μm are arranged are arranged horizontally. Although three are not shown, they have sensitivity to red (R), green (G), and blue (B).

  The light receiving section 60 can be moved by a motor (not shown) along the longitudinal movement guides 51a, 51b, 51c and the lateral movement guides 52a, 52b provided in the scanning section 50, and the horizontal plane, the vertical axis and the vertical plane. It can be rotated by another motor. Each motor is controlled by the PC 30. Note that the distance between the center of the color line sensor 61 and the optical system 10 to be measured does not vary even when the light receiving portion rotates.

  Next, the measurement method will be described with reference to the drawings. FIG. 5 is a diagram for explaining the measurement procedure in this embodiment.

  Step 1 is setting measurement conditions. The switch of each part operation part is turned on, and the focal length of the test lens and the target information for measuring the projection magnification are selected from the memory and made available to the PC.

  Step 2 is a measurement distance setting. Since the scanning unit 50 is normally fixed, the distance from the color line sensor 61 is set by the movement of the movable loading table 40 according to the measurement conditions.

  Step 3 is a stage for optical axis adjustment preparation. After the illumination optical system in the projection unit 20 is removed, the laser illumination light source is inserted. Further, the circular diffraction grating 28 is arranged at the target position, and the laser illumination light source is turned on. The laser beam that has passed through the diffraction grating draws many concentric circles around the central axis as shown by the arrow in FIG. Note that the diffraction grating is not limited to a circular shape but may be a rectangular shape that is vertically and horizontally. Further, the parallelism and concentricity of the test object mounting portion 24 and the target (chart) portion 25 are set by another method.

  Step 4 is horizontal optical axis alignment. In combination with step 5, the optical axis of the test optical system and the evaluation surface scanned by the light receiving unit 60 are set to be orthogonal to each other. First, the light receiving unit 60 is arranged at the center of the diffraction image, and the remaining two are arranged at an equal interval in the horizontal plane. At this time, the adjustment is completed if a diffraction image having the same phase is projected on the center of the light receiving unit arranged outside. If they are different from each other, the shift adjusting unit 23 of the projection unit is operated to adjust the same interval. At this time, since the center also moves, the setting position of the light receiving unit 60 is adjusted again. By repeating this, the inclination in the horizontal plane is completed.

  Step 5 is vertical optical axis alignment. The light receiving unit 60 is arranged at the center of the diffraction image, and the remaining two are arranged at arbitrary equal intervals in the vertical plane. The setting method may be performed with respect to the vertical while operating the adjusting unit 22 in the same manner as in Step 4. For adjustment of the optical axis, a dedicated tool lens adjusted so that the optical axis is aligned with the lens mounting portion to be examined may be used, but this is disadvantageous in terms of time and cost. The method was used.

  Step 6 is a projection preparation. The laser illumination light source in the projection unit 20 is retracted, the light source unit 21 is mounted, the circular diffraction grating 28 at the target position is removed, and the target 25 is inserted. Further, the test optical system is attached to the test object mounting portion 24.

  Step 7 is the angle adjustment of the light receiving part. The light receiving unit is tilted around the center of the light receiving element by the rotation of the servo motor based on the numerical value stored in the PC in the entrance pupil direction of the test optical system. In addition, if the incident angle is small, it is not necessary to give an inclination in order to omit the subsequent processing.

  Step 8 is brightness adjustment and focusing. The light source unit 21 is switched on to illuminate the target and project it to the center of the light receiving unit 60 arranged at the center of the evaluation screen. At this time, since the slit image is horizontal (or vertical), in order to make the line sensors orthogonal, the light receiving unit 61 is rotated in the evaluation plane as necessary to align the position. Since the slit image intensity distribution is displayed on the PC display unit 31, the brightness is adjusted to a level lower than the saturation point of the line sensor by a means not shown. Further, the focus adjustment mechanism of the target is operated from the PC 30, and the position where the slit image intensity distribution of the PC display unit 31 becomes high and the width becomes narrow is determined while changing the distance from the test optical system. Although the slit image intensity distribution increases as the focus is adjusted, the maximum value should always be suppressed to about 80 to 70% with a margin from the saturation point. Although the focal position differs for each of R, G, and B colors, the focal position is usually determined by a slit image of G color.

  Step 9 is capturing a projected image. The intensity distribution orthogonal to the projected slit is taken in multiple times as measured values for each RGB color of the image, and the average value is recorded in the memory on the PC.

  Step 10 is correction of the projected image. The captured data is normalized to a fixed value with a linearity correction and a maximum brightness level based on a table whose brightness level is separately determined. Next, correction is performed for the enlargement magnification based on the projection distance or the enlargement magnification measured separately. Further, since the slit image width is reduced in proportion to the angle θ at which the light receiving unit is tilted, the distance between the sensor elements corresponding to the measured slit image width is corrected by dividing by cos θ. At this time, if there is an inclination in the oblique direction with respect to the evaluation surface, that is, up and down and left and right with respect to the evaluation surface, division is performed twice according to both angles.

  Step 11 is correction of the light source color. Correction according to the weight ratio for the color of the light source to be evaluated based on a table obtained in advance as the intensity ratio of each RGB sensor for the color temperature (relative spectral intensity distribution) used for measurement and the color temperature actually used Do. Next, the RGB intensity distribution is converted into a luminance value by the NTSC luminance conversion method and stored in the memory. The conversion method can be arbitrarily selected depending on the purpose, and may be stored for each RGB.

  Step 12 is an MTF calculation. The intensity distribution of the projected slit image is called LSF, and the output form is as shown in FIG. The horizontal axis represents the size of the projected image obtained from the light receiving element pitch, and the vertical axis represents the normalized output value. The LSF obtains the MTF by the calculation means through the slit and projection magnification correction calculation shown in Step 11. In general, Fourier transform is performed on discrete frequencies, and the MTF for each frequency is obtained based on the ratio to the ideal Fourier image obtained from the slit width.

  Step 13 is the movement of the light receiving unit. After the slit image is completely stored in the memory in step 9, the light receiving unit moves to the determined next position. The three light receiving units alternately perform step 7 and step 9 based on the movement information to the PC in advance, move to the next measurement point in the evaluation screen, and face the exit pupil of the optical system to be measured. Perform the operation. Thereafter, Step 10 to Step 12 are executed instantaneously.

  Since the three light receiving units are arranged, the movement controlled by the PC and the image capturing are performed in parallel instead of individually performing each step as described above, and the effect of shortening the moving distance by arranging three light receiving units is provided. Overlap measurement time can be greatly reduced.

  Step 14 is a display of measurement data. The result of obtaining the MTF by the calculation means in the PC is displayed as a frequency characteristic value as shown in FIG. 9, for example, and can be printed if necessary.

Step 15 is to change the measurement conditions. Steps 7 to 14 are repeated by performing necessary measurement conditions such as vertical / horizontal conversion of the measurement slit, changing the shift amount of the evaluation screen, changing the aperture stop, and the like. Note that when changing the shift amount of the evaluation screen and measuring at an angle larger than the measurement range shown in FIG. 1, for example, a large angle such as θ2, the projection unit 20 is rotated 90 degrees and expanded in the horizontal direction and measured in the same way. Good.
The measurement is the end step.

(Example 2)
A second embodiment of the present invention will be described with reference to the drawings. FIG. 4 is a diagram showing an outline of the entire configuration in the second embodiment of the present invention. The test optical system uses the same off-axis optical system as in the first example, and a target (slit) image is created and displayed on a light modulator such as an LCD on a PC for the front projector image projected in an upwardly biased form. An example of measuring the optical performance of the projected image intensity distribution using an arithmetic processing unit will be described.

  The configuration is such that the projection unit 20 described in the first embodiment is removed and a test projector 70 is arranged, and the same is the case with 50 scanning units and 30 PC (system control / arithmetic unit) units.

  The measurement method is almost the same as the method described in the first embodiment. However, the operations related to optical axis alignment from step 3 to step 7 are performed by the conventional method because the optical system is incorporated in the projector. Become. The calculation of the MTF is also relative to the projection optical system when the method described in the first embodiment is used, but a sufficient absolute value can be obtained as the MTF evaluation value for the projector as a whole.

It is a figure which shows the outline of the whole structure in the 1st Example of this invention. It is a figure which shows the outline of the whole structure of the scanning part at the time of seeing from the test optical system side. It is a figure which shows the structure which changed the projection part for optical axis adjustment. It is a figure which shows the outline of the whole structure in the 2nd Example of this invention. It is a step figure showing a measuring method. It is a figure of the example showing the frequency characteristic of MTF. It is a figure which shows the outline of the whole structure in the conventional Example. It is a figure which shows the example of a line image intensity distribution (LSF). The figure which shows the example of the change of LSF by the incident angle to a light receiving element.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Optical system to be measured 20 Projection unit 21 Light source unit 25 Target (chart) unit 30 PC (system control / arithmetic unit)
40 Moving platform 50 Scanning section 51 Vertical movement guide 52 Horizontal movement guide 60 Light receiving section 61 Color line sensor 70 Coaxial lens 80 Front projector

Claims (7)

  The target (slit) placed on the focal plane of the optical system to be measured is enlarged and projected by the illumination means, and the projected image intensity distribution is received by the light receiving means placed in a mechanism that can scan vertically and horizontally within the plane of the evaluation distance, and the performance is measured. In the apparatus, the light receiving means can rotate in a vertical plane and around a horizontal / vertical axis, and receives an output distribution of a target image corresponding to a measurement purpose in a state tilted in the exit pupil direction of the optical system to be measured. An optical system performance measuring apparatus and method for measuring the performance of an optical system by performing correction according to an inclination angle and processing according to a measurement purpose by an arithmetic means.   The light receiving element used in the light receiving means receives light at a plurality of wavelengths having different wavelength ranges, and each received light intensity is corrected according to the weight ratio with respect to the color of the light source to be evaluated, and then the optical system performance is calculated. The optical system performance measuring apparatus and method according to claim 1.   The target (slit) placed on the focal plane of the optical system to be measured is enlarged and projected by the illumination means, and the projected image intensity distribution is received by the light receiving means placed in a mechanism that can scan vertically and horizontally within the plane of the evaluation distance, and the performance is measured. An optical system performance measurement comprising a projection optical system for adjusting an optical axis different from the optical system to be measured in order to match the parallelism between the evaluation projection surface and the target surface Apparatus and method thereof.   The projection optical system means for adjusting the optical axis according to claim 3 uses a laser light source and a diffraction grating chart, and the symmetrical spread of the diffraction grating measures the difference between the left and right or upper and lower centers on the projection evaluation surface. An optical system performance measuring apparatus having a means for adjusting the whole projection system in order to eliminate the deviation, and a method therefor.   In an apparatus for measuring performance by enlarging and projecting a target placed on the focal plane of an optical system to be measured by an illuminating means, and receiving a projected image intensity distribution by a light receiving means arranged in a mechanism capable of longitudinal and lateral scanning within the plane of the evaluation distance. And the means for illuminating the optical system to be measured and the target disposed on the focal plane are configured integrally, and the distance between the projection evaluation surface and the target can be set, and can be used in vertical and horizontal movements and horizontal and vertical planes. An optical system performance measuring apparatus and a method thereof according to claim 3 and claim 4.   In an apparatus for measuring performance by enlarging and projecting a target placed on the focal plane of an optical system to be measured by an illuminating means, and receiving a projected image intensity distribution by a light receiving means arranged in a mechanism capable of longitudinal and lateral scanning within the plane of the evaluation distance. An optical system performance measuring apparatus and method for creating and displaying a target image on a light modulation element such as an LCD by a PC, and measuring and evaluating the optical performance of the projected image intensity distribution by the light receiving means and the arithmetic processing unit.   The target (slit) placed on the focal plane of the optical system to be measured is enlarged and projected by the illumination means, and the projected image intensity distribution is received by the light receiving means placed in a mechanism that can scan vertically and horizontally within the plane of the evaluation distance, and the performance is measured. 7. The optical system performance measuring apparatus and method according to claim 1, 3, 5, and 6, wherein said apparatus comprises a plurality of said light receiving means.

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