JP2005345904A - Image generation apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve image quality by fully reducing light intensity unevenness and color unevenness of an image, in an image generating apparatus which has a structure of projecting a two-dimensional intermediate image, obtained after optical scanning of a one-dimensional image. <P>SOLUTION: The image generation apparatus 1 has an optical modulation part 4 using a one-dimensional optical modulation element and a driving means 13 thereof, and sends the one-dimensional image to an optical scanning means 18, after modulating light by using the one-dimensional optical modulation element. The two-dimensional intermediate image, formed by the optical scanning, is projected with a projection optical system 9. A light intensity distribution measurement means 15 is provided to measure an intensity distribution in the vertical direction, corresponding to the major axis direction of the one-dimensional optical modulation element and in the horizontal direction orthogonal to the vertical direction by receiving the light emitted from the projection optical system 9, when an image for measurement of the light intensity is displayed. A correction means 20 is provided to correct a driving signal for the one-dimensional optical modulation element, on the basis of the measured data so that the occurrence of the unevenness in the light intensity or the like is not generated in the vertical and the horizontal directions of the image. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a technique for reducing two-dimensional luminance unevenness, color unevenness, and the like related to a display image in application to an image generation apparatus (or image output apparatus) including a projector, a printer, and the like.

  An image generation apparatus such as a projector is known to include a spatial light modulation element using a liquid crystal panel or the like and an optical system including a projection lens so as to project a two-dimensional image on a front screen ( For example, refer to Patent Document 1 regarding countermeasures against temporal changes of spatial light modulation elements).

  As a method for increasing the resolution of an image, a method using a one-dimensional spatial modulation type image display light modulation element is known. Examples of the one-dimensional spatial modulation type light modulation element include a grating light valve (hereinafter referred to as “GLV”) developed by Silicon Light Machine (SLM) of the United States. This GLV is composed of a reflective diffraction grating, and a plurality of movable ribbons are arranged at a predetermined interval, and a fixed ribbon is arranged between adjacent movable ribbons. Then, by applying a drive voltage between the common electrode and the movable ribbon, the movable ribbon moves, and a diffraction grating for incident light is configured.

  In an image projector or the like using such a one-dimensional light modulation element, a one-dimensional image obtained by modulating light from a laser light source is converted into a one-dimensional direction (corresponding to the vertical direction of the screen) by an optical scanning unit such as a galvanometer. A two-dimensional image can be formed by projecting on a screen while scanning along a direction orthogonal to.

  The optical positional relationship between the optical scanning means and the projection lens (projection lens) includes the following two forms.

(I) Configuration for performing optical scanning after projection of a one-dimensional image (II) Configuration for projecting a two-dimensional intermediate image after optical scanning.

  First, in the form (I), a one-dimensional image projection optical system including a projection lens is provided, and light (linear intermediate image) transmitted through the projection lens is scanned on the screen by the light scanning means. Expand and display as a two-dimensional image.

  In the mode (II), a two-dimensional image projection optical system including the projection lens is used to form a two-dimensional intermediate image by scanning with an optical scanning unit and then enlarge and project the intermediate image with the projection lens. Have.

  In the case of the form (II), for example, a corresponding one-dimensional light modulation element is provided for each of the three primary color laser light sources, and light modulated using the element is collected through a Schlieren filter. After that, the laser beam can be optically scanned with a scanner (galvanometer mirror) to form a two-dimensional image intermediate image, which can be projected on a screen via a projection lens.

  The advantages obtained by adopting (II) in comparison with the above form (I) are as follows.

-It is not necessary to change the rotation angle (swing angle) of the galvano mirror in conjunction with the zooming operation of the projection lens.-The area size of the reflecting surface of the galvano mirror can be reduced. Able to reduce image curvature.

JP-A-6-281950

  By the way, compared with the case where the one-dimensional projection optical system of the form (I) enlarges and projects a linear one-dimensional intermediate image, the two-dimensional projection optical system of the form (II) Since it is necessary to carry out enlargement projection, a decrease in the amount of peripheral light within the projection lens is a problem.

  As an example, in an application such as a digital cinema, when the aspect ratio of the screen is “2.35: 1”, the effective length in the major axis direction of the one-dimensional light modulation element (for example, GLV element) is 28 mm. The horizontal size is about 66 mm (= 28 × 2.35 = 65.8). That is, when an intermediate image having a size of 66 mm in width and 28 mm in length is projected on a screen by a two-dimensional projection optical system, uneven brightness and color unevenness are minimized as long as the decrease in the amount of peripheral light in the projection lens is sufficiently suppressed. In order not to occur, a large projection lens is required.

  Alternatively, the detection information of the light intensity distribution obtained by the light detection means attached to the screen, the data obtained by photographing the test image on the screen using the image sensor, etc. are acquired so that the illuminance distribution on the screen becomes uniform. In the method of correcting the driving signal of the one-dimensional light modulation element, it is difficult to suppress the occurrence of uneven brightness and color unevenness to a sufficient level, or the control and configuration for that purpose are complicated. There is.

  Factors that affect the irradiation light distribution in the direction on the screen (vertical direction) corresponding to the major axis direction of the one-dimensional light modulation element include the modulation characteristics of the individual elements constituting each pixel in the direction and Variations in manufacturing, the profile of illumination light irradiated to each element, and the like are listed, and the combined characteristics are reflected in the illumination state on the screen. Therefore, if the intensity distribution of the modulated light corresponding to each pixel position is examined and the drive signals of the constituent elements are corrected so as to obtain a uniform distribution, the major axis direction and the direction of the one-dimensional light modulation element can be obtained. It is possible to suppress the occurrence of luminance unevenness and color unevenness in the vertical direction of the screen corresponding to.

  However, in the form (II), it is necessary to reduce the unevenness of the illumination state in the direction on the screen (lateral direction) corresponding to the light scanning direction by the galvanometer mirror. In other words, unless there is a means to correct the decrease in the amount of peripheral light caused by vignetting in the projection lens due to light scanning in the direction, brightness unevenness and color unevenness are sufficiently reduced for the two-dimensional image after projection. Difficult to do.

  In view of this, the present invention provides an image generating apparatus having a configuration for projecting a two-dimensional intermediate image obtained after optical scanning of a one-dimensional image, sufficiently reducing unevenness in light intensity, color unevenness, and the like related to the generated image. It is an object to improve.

  In order to solve the above-described problem, the present invention receives the light emitted from the projection optical system when the light intensity measurement image is displayed by controlling the driving means of the one-dimensional light modulation element, and receives the primary light. Based on the measurement data from the light intensity distribution measuring means for measuring the intensity distribution in the first direction corresponding to the major axis direction of the original light modulation element and the second direction orthogonal to the direction, and the measurement data from the light intensity distribution measuring means Correction means for equalizing the light intensity in the first direction and the second direction by correcting the drive signal related to the one-dimensional light modulation element and controlling the drive means is provided.

  Therefore, in the present invention, the emitted light can be measured immediately after the projection optical system, and the display image in the vertical direction and the horizontal direction corresponding to the first direction and the second direction is based on the measurement data. Luminance unevenness, color unevenness and the like can be removed by correction.

  According to the present invention, the reduction in the amount of light in the periphery of the image is suppressed and uniformization is achieved, and unevenness in light intensity, color unevenness, and the like can be sufficiently reduced, which is effective in improving image quality. Further, it is possible to improve the uniformity of the intensity distribution in the second direction without requiring a large and expensive projection lens.

  In the pre-stage of performing projection for image display, the measurement image is output and measured as an entire two-dimensional intermediate image, and intensity distribution measurement is performed before image projection, and correction processing based on measurement data can be performed. .

  Further, in the embodiment in which the measurement image is incorporated into a part of the two-dimensional intermediate image and output for measurement, the intensity distribution measurement can be performed simultaneously with the image display, so that correction processing can be performed in real time based on the measurement data.

  In order to be able to detect the intensity distribution of the emitted light from the projection optical system regardless of the incident angle and position, the light intensity distribution measuring means averages after collecting the emitted light from the projection optical system. A configuration in which the converted light intensity is detected is preferable. In that case, an integrating sphere, an optical element for condensing the light emitted from the projection optical system and introducing it into the integrating sphere, and a light detecting means for detecting the light intensity averaged by the integrating sphere are used. .

  In order to measure the intensity distribution in the second direction, the light scanning position in the second direction is changed by controlling the optical scanning means when measuring the light intensity distribution with respect to the light emitted from the projection optical system. The measurement data obtained by measuring the light intensity distribution for each light scanning position is sent to the correction means. Then, the correction unit corrects the drive signal for each scanning position in the second direction based on the measurement data of the light intensity distribution obtained for each optical scanning position. As a result, the drive signal is corrected for each scanning position in the second direction, and the light intensity distribution can be made uniform.

  In the configuration in which the moving device is provided for the measuring device constituting the light intensity distribution measuring means, the measuring device is moved to a position near the projection optical system when measuring the light intensity distribution, and the light emitted from the projection optical system is measured. Is introduced into the measuring apparatus, and the measuring apparatus is moved to a retracted position that does not affect the display during image projection. The measurement position and the retreat position can be positioned by the movement control of the measurement device. When measuring the light intensity distribution for the light emitted from the projection optical system, the position of the measuring device is controlled according to the optical scanning position in the second direction, allowing measurement that follows the change in the optical scanning position. become. If the measuring device is positioned in the vicinity of the projection optical system when image projection is not performed or the apparatus is not operated, the projection optical system is protected and safety measures against high-intensity light (prevention of laser failure, etc.) Can be taken.

  In a configuration in which the measuring device constituting the light intensity distribution measuring means is fixedly installed, a movable type for introducing light into the measuring device by changing the optical path of the emitted light of the projection optical system when measuring the light intensity distribution It is preferable to provide the optical element. That is, it is possible to perform measurement using a movable optical element by installing the measuring device in a place where it does not interfere with image projection. Alternatively, when performing image projection, by providing an optical element for introducing a part of the emitted light of the projection optical system into the measuring device, the image can be projected as it is for the remaining part of the emitted light. Measurement can be performed while displaying an image.

  In the light detection means constituting the light intensity distribution measurement means, if a configuration including a filter that transmits only light having a different wavelength for each light source and a light sensor that receives light transmitted through the filter is employed, Since different light can be measured simultaneously, it is effective for shortening the processing time.

  In addition, when applied to an image display device that includes a one-dimensional light modulation element, a spatial filter, an optical scanning unit, and a projection optical system, and displays an image on a screen, it is possible to realize high performance and improved image quality. .

  The image generation apparatus according to the present invention has an object to guarantee high image quality by correcting the intensity unevenness and the color unevenness two-dimensionally in the configuration adopting the above-described form (II). A one-dimensional image formed by an original spatial modulation type light modulation element or the like is scanned by an optical scanning means such as a galvanometer to form a two-dimensional intermediate image, and this is projected on the front projection type or rear projection type. The present invention can be applied to an image display device or an image output device such as a printer.

  FIG. 1 illustrates an outline of a basic configuration when an image generation apparatus 1 according to the present invention is applied to a front projection type (front projection type) image display apparatus.

  First, the configuration of the optical system will be described. Light emitted from the light source 2 reaches the light modulation unit 4 via the illumination optical system 3, and the light modulated here passes through the color synthesis unit 5 and the spatial filter 6. The scanning unit 7 is reached.

  As the light source 2, for example, laser light sources 2R, 2G, and 2B using a semiconductor laser, a solid-state laser, and the like are provided for each color of R (red), G (green), and B (blue). In response to power supply from a power supply unit (not shown), laser beams having wavelengths corresponding to the respective colors are output.

  The illumination optical system 3 has a function of converting a beam output from each laser light source into a one-dimensional linear beam, and is configured using a beam expansion optical system, a line generator, or the like. Note that optical systems 3R, 3G, and 3B corresponding to the respective colors of R, G, and B are used.

  The light modulation unit 4 is configured by using one-dimensional light modulation elements 4R, 4G, and 4B corresponding to R, G, and B colors, and is made uniform in intensity distribution (so-called so-called optical systems 3R, 3G, and 3B). Each element is irradiated with a linear beam having a “top hat” distribution.

  In an application example using a GLV element as a one-dimensional light modulation element, in the case of a reflective diffraction grating, a plurality of movable ribbons and fixed ribbons are alternately arranged along a predetermined direction. For example, when six ribbon elements constituting one pixel are provided and every three movable ribbons and every other fixed ribbon are arranged, for example, 1080 pixels for one line 6480 ribbon elements are arranged along the one-dimensional direction (major axis direction). For the first surface, which is the surface of the movable ribbon, and the second surface, which is the surface of the fixed ribbon, with respect to the laser light irradiation surface, aluminum copper (AlCu) alloy or the like is used, and each surface is arranged alternately. In addition, the movable ribbon is moved in response to a drive signal from a drive means (13) described later, and the position of the first surface is controlled in a direction along the irradiation direction of the laser beam. That is, the movable ribbon moves with a displacement amount corresponding to the application of the drive voltage corresponding to the image signal, and in this state (so-called pixel on), a reflection diffraction grating for incident light is formed (generation of first-order diffracted light). . Further, in a state where the displacement amount is made uniform with the fixed ribbon without moving the movable ribbon (so-called pixel off), the first-order diffracted light is not generated (only regular reflection with respect to the incident light). Note that the use of the GLV element provides advantages such as high-speed operation control and that it can be driven with a low operating voltage when displaying a high resolution image with a wide bandwidth.

  In this way, the reflected light and diffracted light of the illumination light irradiated on the one-dimensional light modulation element are generated, and the color combining unit 5 combines the modulated color lights and sends them to the spatial filter 6.

  The spatial filter 6 has a function of selecting a diffracted light component of a specific order, and in this example, a schlieren filter is used to extract ± first-order diffracted light from light modulated using a one-dimensional light modulation element. (0th-order light not used for image display is shielded).

  For example, a galvanometer is used for the optical scanning unit 7 at the next stage, and receives a one-dimensional image of incident light to form a two-dimensional intermediate image. That is, when the formation direction of the one-dimensional image is the “first direction”, the direction corresponds to the major axis direction of the one-dimensional light modulation element, and the “second direction” is orthogonal to the first direction. A two-dimensional intermediate image is formed by performing optical scanning along the “direction of”. Note that the scanning method includes a unidirectional scanning method and a bidirectional scanning method. In the former method, for example, the left edge of the display screen is set as the scanning start position, the right edge is set as the scanning end position, and the vertical line extending in the first direction from the left edge is started. After scanning along the second direction, when the right edge is reached, the light returns to the left edge again and the optical scanning is repeated. In the latter method, the left edge and the right edge of the display screen are set as the scanning start position and the scanning end position. For example, optical scanning is started from the left edge, and the vertical line extending in the first direction is the first line. After scanning along the two directions, when the right edge is reached, light scanning is performed in the opposite direction, and when the original left edge is reached, the light scanning is started again from the left edge.

  A two-dimensional intermediate image obtained by such optical scanning passes through the light diffusing unit 8 and is then projected onto the screen “SCN” by the projection optical system 9 to display an image.

  The light diffusing unit 8 is provided to obtain diffused light using a diffuser for reducing speckle (noise), and the projection optical system 9 is a two-dimensional projection optical system including a projection lens. It is.

  A light detection device 10 is provided for the projection optical system 9 to receive light emitted from the projection optical system and detect the light intensity (details will be described later).

  Next, an image processing system and a control system will be described.

  The video signal indicated by “VIDEO” in the figure is sent to the correction processing unit 12 via the signal processing unit 11.

  In the signal processing unit 11, the video signal is converted from a color difference signal to an RGB color signal. When a nonlinear characteristic such as a γ (gamma) characteristic is given, the color space is converted to the linear characteristic by performing reverse correction, and then the color space is used for the color reproduction range of the illumination light source. Perform the conversion process.

  The correction processing unit 12 performs signal correction with reference to information from a correction data calculation unit (16) described later, and controls a drive signal to the one-dimensional light modulation element generated according to the image signal. To do.

  The drive means 13 is provided for driving the one-dimensional light modulation element, includes an element drive circuit, generates a drive signal in accordance with a command from the correction processing unit 12, and generates the one-dimensional light of the light modulation unit 4. Each is supplied to a modulation element. The laser light of each color is modulated by driving control of the light modulation element by the driving unit 13.

  The light intensity distribution measurement processing unit 14 is provided for processing the detection information from the light detection device 10 to measure a two-dimensional light intensity distribution, and together with the light detection device 10, a light intensity distribution measuring means. 15 is configured. That is, upon receiving the light emitted from the projection optical system 9, the intensity distribution in the first direction and the second direction orthogonal to the direction is measured, and the measurement result is sent to the correction data calculation unit 16.

  The optical scanning control unit 17 constitutes an optical scanning unit 18 together with the optical scanning unit 7, and performs control for scanning a one-dimensional image obtained by modulating light using a one-dimensional light modulation element. That is, a control signal is sent to the optical scanning unit 7 in accordance with a synchronization signal indicated by “SYNC” in the drawing and a command from the light intensity distribution measurement processing unit 14 (an optical scanning position instruction signal), and its operation (rotation of the galvanometer mirror). ) To control.

  In this example, the correction data calculation unit 16 constitutes the correction unit 20 together with the storage unit 19 and the correction processing unit 12 and is realized using hardware such as a CPU (Central Processing Unit) and a memory and a processing program. . That is, the correction unit 20 corrects the drive signal related to the one-dimensional light modulation element based on the measurement data from the light intensity distribution measurement processing unit 14. Although a specific correction method will be described in detail later, correction for equalizing the light intensity in the first direction and the second direction is performed by controlling the driving unit 13.

  The correction data calculated based on the measurement data sent from the light intensity distribution measuring means 15 to the correction data calculation unit 16 is sent out by the correction processing unit 12 and referred to. For example, in order to compensate for the decrease in the amount of peripheral light due to the vignetting in the projection lens described above, the degree of decrease in the light intensity is quantified from the measurement data, and the optical scanning position is obtained so that a uniform light intensity can be obtained. One-dimensional light modulation element drive control while referring to the correction amount at the time of image projection after calculating the correction amount corresponding to each time and performing real-time processing or temporarily storing the calculated correction amount in the storage means 19 I do.

  Examples of the configuration in the case where the light intensity measurement image is displayed and measured by the light intensity distribution measuring means 15 include the following examples.

(A) As a preparation stage of image projection, a measurement image is output from the projection optical system 9 at a stage where calibration (calibration), initial setting, and the like are performed, and detected by the light detection device 10 (B) Image projection is performed On the other hand, a mode in which an image for measurement is output from the projection optical system 9 and detected by the light detection device 10 so as not to affect the image display. (C) A mode in which (A) and (B) are combined.

  First, in the form (A), in a preliminary stage of performing projection for image display, the measurement image is output as a whole two-dimensional intermediate image from the projection optical system 9 and the intensity distribution is measured by the light intensity distribution measuring means 15. .

  In the case where a measurement image is formed before the image projection display and is detected by the light detection device 10, for example, a measurement image signal (test image signal) indicated by “TEST” in FIG. 13 to drive the one-dimensional light modulation element. As the image signal, a signal at a predetermined level assuming that there is no luminance unevenness or color unevenness is used. For example, as indicated by “TEST1” in FIG. 2, a signal indicating a constant value in the image display range indicated by “G1” may be used. In the uppermost display screen, the direction indicated by arrow A (vertical direction) corresponds to the first direction, and the direction indicated by arrow B (lateral direction) corresponds to the second direction. The intensity distribution measured using the light detection device 10 in a state before correction related to the drive signal of the one-dimensional light modulation element has nonuniformity in the A direction and the B direction.

  In the form (B), the measurement image is incorporated into a part of the two-dimensional intermediate image, and then output from the projection optical system 9 so that the intensity distribution can be measured by the light intensity distribution measuring means. It is possible to correct the light intensity sequentially or periodically while displaying. For example, a measurement image signal is periodically inserted every 100 frames of image display, and the intensity measurement is performed with a period that is not recognized by the observer's eyes, or on the screen There is a mode in which the intensity measurement is performed at the timing of optical scanning outside the image display range. In the latter case, as shown in “TEST2” in FIG. 2, the measurement image is set to a frame or a frame of a certain period with respect to the region “G2” located outside the image display range G1 in the B direction. What is necessary is just to measure the intensity | strength of the projection light to the said area | region while providing. In this case, the test signal is included in a part of the image signal (see the broken line in FIG. 1), and only the intensity distribution in the peripheral area of the image can be measured. However, in the B direction, it is only necessary to compensate for the decrease in the peripheral light amount. Therefore, it is possible to correct the light intensity in the image display range according to the measurement data in the peripheral area (that is, when the output of the laser light source is constant, the light intensity is increased unless the light scanning speed is changed). Since the direction cannot be corrected, the drive signal to the one-dimensional light modulation element is corrected so as to increase the uniformity by reducing the light intensity in the image display area based on the light intensity in the peripheral area. ). In the case of controlling the output of the laser light source in order to increase the amount of light in the peripheral area, it is necessary to give sufficient consideration to the influence of wavelength fluctuation and controllability.

  In the form (B), it is necessary to take measures against the influence on the display when the measurement image signal is projected as a projected image, but it is possible to perform the correction process while displaying the image.

  In the above-described form (C), for example, the light intensity distribution is initially corrected according to the form (A), and further correction processing can be performed in parallel with the image display, so that it is possible to cope with changes over time, changes in the surrounding environment, etc. It is. In the form (A), the measurement image is formed as an entire two-dimensional intermediate image, whereas in the form (B), the measurement image is formed by being incorporated into a part of the two-dimensional intermediate image. It is suitable for simple measurement, and a method of selectively adopting both forms according to setting conditions such as a display purpose and a projection distance is also possible.

  Incidentally, for the synchronous control of the drive timing of the one-dimensional light modulation elements 4R, 4G, 4B and the rotation phase (light scanning position) of the galvano mirror constituting the light scanning unit 7, known control means using a CPU is used. Is under the control of

  FIG. 3 is a schematic view illustrating the main part of the optical system according to the image generating apparatus 1.

  One-dimensional light modulation elements 4R, 4G, and 4B corresponding to R, G, and B colors are respectively irradiated with light from an illumination light source (not shown). Each light source uses a laser that irradiates each color laser beam. Each laser beam is shaped into a linear beam by a line generator or the like and then irradiated to each element 4R, 4G, 4B. The

  Each modulated laser beam is optically synthesized using the color synthesis mirrors 5a and 5b, and then reaches the galvano scanner (mirror) 22 via the Offner relay system 21 and undergoes optical scanning.

  The Offner relay system 21 is configured by using a primary mirror (concave mirror) 21a and a secondary mirror (convex mirror) 21b. The light after color synthesis is first reflected by the primary mirror 21a and then the secondary mirror. After being reflected by 21 b and further receiving the second reflection by the primary mirror 21 a, it is emitted toward the galvano scanner 22. By providing the secondary mirror 21b with the function of a schlieren filter (the function of separating the specularly reflected light component and the diffracted light component and extracting only the diffracted light of a specific order) or by attaching the schlieren filter to the secondary mirror 21b The 1st-order diffracted light and the 0th-order diffracted light can be separated and the 1st-order diffracted light can be selected and passed. For example, a configuration in which a Schlieren aperture is formed in the secondary mirror 21b to transmit unnecessary light components (0th-order light, second-order diffracted light, etc.) and only ± 1st-order diffracted light is reflected toward the primary mirror 21a. . In this embodiment, the optical configuration is simple, which is suitable for downsizing and the like, and is effective in reducing aberrations.

  The formation direction of the one-dimensional image reaching the galvano scanner 22 from the Offner relay system 21 is a direction perpendicular to the paper surface of FIG. 3, and a two-dimensional intermediate image “g2” is formed by optical scanning. In this example, the field curvature correction optical system 23 is disposed after the galvano scanner 22 to remove the field curvature of the two-dimensional image (that is, the field curvature is rotated around the one-dimensional rotation axis). This is because the two-dimensional image plane with respect to the deflection angle becomes a cylindrical surface with the rotation axis as the central axis in the case of using the optical deflection means.

  The two-dimensional intermediate image g2 after passing through the field curvature correcting optical system 23 is enlarged and projected on the screen by the projection optical system 9, and a measuring device 24 is used to measure the light intensity distribution. This measuring device 24 constitutes the light detecting device 10 of the light intensity distribution measuring means 15 described above, and is installed near the exit port of the projection optical system 9 by manual or automatic control, and the emitted light from the projection optical system 9 After the light is condensed, the averaged light intensity is detected.

  In this example, the optical element 25 for condensing, the integrating sphere 26, and the light detecting means 27 are provided, and the emitted light from the projection optical system 9 is condensed by the optical element 25 and introduced into the integrating sphere 26. The light detection means 27 detects the light intensity averaged by the integrating sphere 26.

  The optical element 25 has a function of collecting and re-imaging all the light emitted from the projection lens, and a condensing lens is used. For example, a lens having a large aperture and a short focal length, that is, a small F number, such as a Fresnel lens, is preferable.

  The laser beam condensed by the optical element 25 is introduced into the inside through an opening (incident port, see FIG. 5) formed in the integrating sphere 26, and the light intensity in the integrating sphere is uniform due to multiple internal reflection. It becomes. That is, the integrating sphere 26 constitutes averaging means, and the averaged light intensity is detected by the light detection means 27. Although a diffusion plate or the like can be used as the averaging means, use of an integrating sphere is preferable when high accuracy is required.

  An optical sensor (photodiode or the like) that constitutes the light detection means 27 converts the light reception signal into an electrical signal and outputs it, and the detection signal is used as basic data for light intensity distribution measurement (the light intensity distribution measurement processing unit 14). To be processed.)

  Examples of the installation form of the measuring device 24 include the following examples.

(1) Configuration form in which the measurement apparatus can be attached to the main body of the image generation apparatus (2) Configuration form in which position control of the measurement apparatus can be performed using moving means such as a movable stage (3) Measurement apparatus (4) The position of the measuring device is fixed. (4) The position of the measuring device is fixed. In this configuration, the optical path is deflected using an optical element such as a movable mirror only when measuring the light intensity distribution. A configuration in which a part of the projection light is guided to the measuring device using an optical element such as a partial reflection mirror so that the light intensity distribution can be measured while projecting the image.

  First, in the above (1), a configuration is used in which the measuring device is installed in the main body only during the measurement of the light intensity distribution using the measurement image, and the measuring device can be removed after the measurement.

  In (2) above, the moving means of the measuring device 24 is provided, and the measuring device is moved to a position near the projection optical system 9 when measuring the light intensity distribution. Then, light emitted from the projection optical system 9 is introduced into an integrating sphere 26 in the measuring device 24.

  For example, in FIG. 3, a moving mechanism including two movable stages 28 and 29 constitutes a moving unit of the measuring device 24. Each movable stage can move along a direction orthogonal to the main optical axis of the projection optical system 9 (a direction parallel to the second direction, see arrow M in the figure). Thus, the first movable stage 28 is mounted on the second movable stage 29.

  The first movable stage 28 has a function of moving the integrating sphere 26 and the light detecting means 27 attached thereto.

  On the second movable stage 29, an optical element 25 such as a condenser lens is mounted, and a first movable stage 28 on which an integrating sphere 26 and a light detecting means 27 are mounted is mounted. The second movable stage 29 has a function of moving the entire measuring device 24, and when measuring the light intensity distribution using the measurement image, the measuring device 24 is moved to a predetermined position (measurement position). The light emitted from the projection optical system 9 is condensed and introduced into the integrating sphere 26 so that the measurement can be performed.

  Then, it is necessary to move the measuring device 24 to a position that does not affect the display during image projection. That is, after the measurement, the measuring device 24 is moved to a position that does not hinder the image projection performed from the projection optical system 9 toward the screen (a retreat position away from the main optical axis of the projection optical system 9). In this way, by providing a mechanism for moving the measuring device 24 between the measurement position and the retracted position, an image is projected from the projection optical system 9 onto the screen or the light emitted from the projection optical system 9 is integrated into an integrating sphere. 26 can be selectively switched. Further, when the image projection is not performed or the apparatus is not operated, it is desirable for the protection of the projection optical system and the safety measure against the laser trouble to design the measurement apparatus 24 so as to always be at the measurement position.

  As the driving means for each movable stage, for example, a linear moving mechanism using a ball screw or nut using a motor as a driving source can be cited. However, in the application of the present invention, not limited to this, various moving mechanisms are available. Or a rotation mechanism can be used. Further, these control circuits, mechanisms, and the like are included in the light detection device 10 or the light intensity distribution measurement processing unit 14 in FIG. 1, and control commands from the processing unit to the light detection device 10 are indicated by broken lines. In accordance with the above, positioning of each movable stage is performed.

  At the time of measuring the light intensity distribution with respect to the light emitted from the projection optical system 9, position control of the measuring device 24 is performed according to the light scanning position. For example, the measurement device 24 is moved by position control related to the second movable stage 29 and set to the measurement position. Then, position control related to the first movable stage 28 is performed according to the scanning position by the optical scanning means using a galvanometer mirror.

  FIG. 4 is a diagram for explaining the relationship between the optical scanning position and the position of the movable stage 28 (shown after the Offner relay system), and FIG. 4A shows the projection state on the center of the screen. B) The projection state to the screen peripheral part is shown. Note that the measuring device 24 has come to the measurement position, and the light emitted from the projection optical system 9 is collected and introduced into the integrating sphere 26 as shown in the figure. Although there is no measurement device 24, the light beam assumed when there is no measurement device 24 is indicated by a broken line.

  The optical scanning position corresponds to the rotation angle of the galvanometer mirror. In the scanning state shown in FIG. (A), the central portion of the two-dimensional intermediate image g2 formed from the galvano scanner 22 via the field curvature correcting optical system 23 is shown. The light passes, and the light emitted from the projection optical system 9 follows the locus indicated by the broken line and is applied to the center of the screen. Further, in the scanning state shown in FIG. (B), light passes through the peripheral portion of the two-dimensional intermediate image g2 formed from the galvano scanner 22 via the field curvature correction optical system 23, and the light emitted from the projection optical system 9 is Then, following the locus indicated by the broken line, the screen edge is irradiated with an inclination angle.

  In order to perform the measurement according to the scanning state, it is necessary to introduce the light emitted from the projection optical system 9 into the integrating sphere 26 while moving the movable stage 28.

  In the following, the focal length of the projection optical system 9 is “f1”, the focal length of the condenser lens used for the optical element 25 is “f2”, and the length (major axis) of the GLV element as the one-dimensional light modulation element The effective length in the direction) will be specifically described as “L”.

  First, the movable stage 29 is moved to install the measuring device 24 in front of the projection optical system 9. At this measurement position, the optical axis of the condenser lens is set to be coaxial with the optical axis of the projection optical system 9. The f2 value is selected so as to satisfy “f2 ≦ f1”.

  Further, the distance from the projection lens constituting the projection optical system 9 to the screen SCN is sufficiently longer than the projection lens aperture, and it can be considered that the light emitted from the projection lens is almost a parallel light flux. At the time of measuring the light intensity, a two-dimensional image reduced to the magnification “f2 / f1” is formed by the condenser lens. For example, when f1 = 100 (mm), f2 = 50 (mm), element length L = 28 (mm), and the scan ratio (aspect ratio) is “2.35: 1”, the rear of the condenser lens ( The size of the two-dimensional image formed on the integrating sphere side is 14 mm in the vertical direction and about 33 mm in the horizontal direction.

  The function of the condensing lens is to condense the light from the projection lens into a sufficiently narrow region and introduce it into the integrating sphere 26, and there is no problem even if the image quality or the like is deteriorated due to aberrations (therefore, It is possible to use not only the Fresnel lens but also an aspherical condenser lens, hologram sheet, light guide rod, concave mirror or the like for the optical element 25).

  The integrating sphere 26 has, for example, a slit-shaped opening 26S as shown in FIG. The vertical width of the opening 26S is approximately the same as the vertical width of the two-dimensional image by the condenser lens (14 mm in the above example), and the horizontal width of the opening is such that it passes through the vertical lines constituting the two-dimensional image. The width is set to the two-dimensional image position.

  When the operation of the galvano scanner 22 (mirror rotation) is stopped in the scanning state of FIG. 4A, the light collected through the condenser lens is a one-dimensional image, and the total amount of light from the opening 26S. It is guided into the integrating sphere 26 and detected. That is, the inner surface of the integrating sphere 26 is coated with a white reflective material mainly made of barium sulfate, and the incident light from the opening 26S repeats multiple reflections. Thereby, the light intensity is averaged and measured by the optical sensor, and the electric signal from the sensor is taken into the signal processing unit in the optical intensity distribution measurement processing unit 14.

  In the one-dimensional light modulation element, the number of measurements corresponding to the number of pixels in the major axis direction is performed. For example, in the case of a GLV element having a 1080 pixel array in the one-dimensional direction, the measurement starts from the first pixel. The measurement data is collected by sequentially performing the process of recording the output of the photosensor by turning on each pixel individually (pixel-on state) up to the 1080th pixel. Thereby, it is possible to measure the light intensity independently for each pixel (however, at this time, the intensity distribution is only measured for one vertical line at a certain light scanning position).

  Next, by changing the optical scanning position by the operation of the galvano scanner 22 (mirror rotation) and performing the same measurement as described above, intensity distribution measurement data is collected for one vertical line at the new optical scanning position. The The optical scanning position corresponds to the second direction, and each time the display position of the vertical line in the horizontal direction of the two-dimensional intermediate image or projection image is changed, the movable stage 28 is moved to move the integrating sphere 26 and the optical sensor. Change the setting position. Thus, at the time of measuring the light intensity distribution for the light emitted from the projection optical system, the optical scanning means is controlled to change the scanning position in the second direction, and the light intensity distribution is changed for each changed scanning position. It is preferable to measure and send the obtained measurement data group to the correction means 20.

  For example, when the operation of the galvano scanner 22 is stopped in the scanning state of FIG. 4B, the attitude of the galvanometer mirror is defined by the angle at which image projection is performed on the peripheral portion on the screen. The position of the image formed by the optical lens moves (shifts) in the lateral direction corresponding to the second direction. Therefore, if the position of the integrating sphere 26 or the optical sensor remains at the position shown in FIG. 4A, light cannot be introduced into the integrating sphere 26, so that the opening position of the integrating sphere 26 and the image position of the condenser lens coincide. As described above, the movable stage 28 is moved and the position of the place corresponding to the light scanning state is determined, and then the light intensity distribution is measured in the same manner as described above.

  By repeating such a process, it is possible to measure the intensity of the projection light directed to an arbitrary image display position on the screen. For example, in the case of horizontal 2048 pixels and vertical 1920 pixels, if the above measurement is performed for 2048 lines, 2048 × 1920 measurement data can be obtained, and the ideal intensity corresponding to the measurement image at any image display position. Deviation from distribution can be quantified. That is, it is possible to collect in detail information for grasping the degree of non-uniformity.

  However, the method of acquiring the measurement data for all the pixels on the 2048 line takes time to process, and when considering the fact that it is not practical, for example, the amount of data to be held increases, a plurality of representative line positions ( It is preferable to select a horizontal position), measure the light intensity for each pixel at the line position, and handle data between lines by interpolation processing.

  For example, m out of 2048 lines are selected at a constant or predetermined interval, and the light intensity is measured for all pixels on each line. Then, for pixels on lines other than m, a primary interpolation equation or a quadratic or higher-order polynomial interpolation equation is used using measurement data relating to each pixel on two lines that are adjacent to each other among m. The intensity can be estimated from the calculated data.

  In the example shown in FIG. 6, the vertical lines VL1 and VL2 are divided into three equal parts between the vertical line VL0 shown at the center position in the horizontal direction (longitudinal direction) of the two-dimensional image and the vertical line VL3 shown at the peripheral position. Is set. That is, after the above measurement is performed on the pixels on each line of VL0 and VL1 to 3, the intensity distribution between VL0 to VL1, VL1 to VL2, and VL2 to VL3 is estimated by the interpolation process. In this example, only the right half of the two-dimensional image has been described. However, when the symmetry of the light intensity distribution in the horizontal direction cannot be assumed, the measurement and interpolation processing is similarly performed for the left half. Also, the vertical line setting interval can be set differently depending on the line position, and the strength can be increased by increasing the number of segments (that is, the number of lines at the measurement position) as necessary. The accuracy sufficient for correction can be obtained.

  In the configuration example described above, the movable stage 28 is moved so as to follow the optical scanning position of the galvano scanner 22 and the movement control of the integrating sphere and the like is performed. However, as shown below, the movable stage 28 is not required. Configuration is also possible.

  FIG. 7 is a diagram for explaining the relationship between the optical scanning position and the setting position of the measuring device 24, and shows the projection state on the center of the screen and the projection state on the periphery of the screen.

  In this example, the difference from the configuration shown in FIG. 3 is as follows.

The movable stage 28 is not provided, and the integrating sphere 26 and the light detection means 27 are placed on the movable stage 29 together with the optical element 25. The integrating sphere 26 has a configuration as shown in FIG. An opening 26P having a size larger than that of the opening 26S is formed.

  That is, the positioning of the measuring device 24 is performed only by moving means including the movable stage 29. And since there is no movable stage 28, it is a little rather than the condensing image (two-dimensional image) by the optical element 25 so that the emitted light from the projection optical system 9 can be introduce | transduced in an integrating sphere even if a light scanning position is changed. An opening 26P having a wide size is formed in the integrating sphere 26 (in the above example, the size of the two-dimensional image is about 14 mm × 33 mm, and an opening having a wider opening than this is required).

  In a state where the movable stage 29 is driven and the measuring device 24 is at the measurement position, the emitted light from the projection optical system 9 is condensed and introduced into the integrating sphere 26. Although there is no projection light, in the figure, a light beam assuming that there is no measurement device 24 is indicated by a broken line.

  First, in the optical scanning state at the time of projection onto the center of the screen, light passes through the center of the two-dimensional intermediate image g2 formed from the galvano scanner 22 via the field curvature correcting optical system 23, and the projection optical system 9 The emitted light follows the locus indicated by the broken line k1 and is irradiated to the center of the screen. At the time of measurement, the emitted light is condensed by the optical element 25, passes through the center of the opening 26P, is introduced into the integrating sphere 26, and the light intensity is measured.

  Further, in the optical scanning state at the time of projection onto the peripheral portion of the screen, light passes from the galvano scanner 22 through the peripheral portion of the two-dimensional intermediate image g2 formed through the field curvature correcting optical system 23, and the projection optical system 9 The emitted light follows the locus indicated by the broken line k2 and is irradiated to the periphery of the screen with an inclination angle. At the time of measurement, the emitted light is collected by the optical element 25, passes through a position near the periphery in the opening 26P, and is introduced into the integrating sphere 26 to measure the light intensity.

  In the measurement process according to the optical scanning state, a moving means such as an integrating sphere is not required, and a condensed image can be guided to the integrating sphere at an arbitrary optical scanning position (galvano mirror angle).

  In this example, the size of the integrating sphere opening 26P is increased, and it is necessary to increase the inner diameter of the integrating sphere in order to increase the accuracy of the integrating sphere, but this is effective for simplifying the moving mechanism and the like.

  Next, the configuration form (3) will be described.

  FIG. 8 shows a configuration example when the optical element 30 for changing the optical path is arranged immediately after the projection optical system 9.

  In this example, the difference from the configuration shown in FIG. 7 is as follows.

The movable stages 28 and 29 are not provided, and the integrating sphere 26 and the light detection means 27 are mounted on the fixed stage 31 together with the optical element 25. The movable reflecting mirror (folded back) immediately after the projection optical system 9 (Mirror) is arranged and the posture is changed between measurement and image projection.

  The measuring device 24 is provided on a fixed stage 31 installed at a location off the optical axis so as not to interfere with image projection by the projection optical system 9.

  In the case of using a movable reflecting mirror as the optical element 30, at the time of measurement, the light emitted from the projection optical system 9 is reflected by the movable reflecting mirror as shown by the solid line in the figure, and the optical path is changed. As indicated by the two-dot chain line in the figure, the movable reflector is retracted so as not to hinder the projection.

  In this example, the position for measurement and the retracted position at the time of image projection can be switched by rotating the movable reflecting mirror manually or by automatic control by a motor mechanism or the like with the one end of the movable reflecting mirror as a rotation fulcrum. .

  That is, at the measurement position, the movable reflecting mirror is disposed on the optical axis of the projection optical system 9, and the light emitted from the projection optical system 9 is reflected by the movable reflecting mirror and deflected at a predetermined angle (for example, 90 °). Thereafter, the light is condensed by the optical element 25 and introduced into the integrating sphere 26 to detect the light intensity. Since the integrating sphere 26 has a large-sized opening 26P shown in FIG. 5B, a condensed image can be guided to the integrating sphere at an arbitrary optical scanning position. Of course, it is possible to perform position control following the optical scanning control using the movable stage 28 as described above. However, in the case where simplification of the mechanism, position accuracy of the movable reflector, etc. are taken into consideration, this example is shown. A configuration form is preferred.

  At the time of image projection, the movable reflecting mirror is moved to a retracted position away from the optical axis of the projection optical system 9, and reflection to the measuring device 24 does not occur.

  As described above, the measuring device 24 is fixed, and the state is changed by using the movable optical element 30, so that the light is introduced into the integrating sphere at the time of measurement and the image is projected onto the screen. The optical path can be easily switched.

  The optical element 30 is not limited to a reflecting mirror, and a reflection type hologram element or diffraction element can also be used. In addition, when a reflecting mirror such as a folding mirror is used, a plane mirror or a concave mirror can be used as appropriate. In particular, when the optical element 30 itself has a light collecting function, the optical element 25 may be omitted. Absent. For example, the light emitted from the projection optical system 9 may be directly introduced into the integrating sphere 26 after being reflected and collected by the reflecting mirror during measurement.

  Next, the configuration form (4) will be described.

  FIG. 9 shows a configuration in which an optical element 32 is disposed immediately after the projection optical system 9 so that a part of the emitted light is transmitted and projected onto the screen and a part of the emitted light is guided to the measuring device 24. An example is given.

  In this example, the difference from the configuration shown in FIG. 8 is as follows.

-A partial reflection mirror must be installed on the optical path instead of the movable reflector.-Light intensity measurement and image projection can be performed simultaneously.

  The measuring device 24 on the fixed stage 31 is installed at a location off the optical axis so as not to interfere with image projection by the projection optical system 9.

  In the case of using a partially reflecting mirror as the optical element 32, the mirror is disposed on the optical axis of the projection optical system 9 in an inclined state, and the movable mechanism as described above is not necessary. That is, a part of the light emitted from the projection optical system 9 is reflected by the partial reflection mirror, collected by the optical element 25 and introduced into the integrating sphere 26 to detect the light intensity. Since the integrating sphere 26 has a large opening 26P shown in FIG. 5B, a condensed image can be guided to the integrating sphere at any optical scanning position (of course, as described above). In addition, a configuration in which the movable stage 28 is used to perform position control following the optical scanning control is also possible.

  Further, most of the emitted light that has passed through the partial reflection mirror is irradiated toward the screen SCN while undergoing optical scanning, as shown by a broken line in FIG. 9, and image projection is performed.

  The partial reflection mirror is provided with a anti-reflection coating on the back surface (outgoing surface side) in order to suppress the generation of noise such as ghosts. Then, it is preferable to apply a coating having a reflectance of several percent on the surface, or to carry out Fresnel reflection without coating (because if the reflectance is too high, the image projection is affected).

  According to the above configuration, real-time processing that sequentially measures light intensity while displaying an image is possible, and can be used in the above-described forms (B) and (C). Then, the light intensity distribution can be measured without the need for moving means related to the measuring device 24 such as a movable stage or a movable mechanism for the movable reflecting mirror. Further, by arranging a partial reflection mirror such as an inclined glass in the subsequent stage of the projection optical system 9, it is possible to suppress the influence on image degradation to a sufficiently small level.

  Next, based on the measurement data of the light intensity distribution obtained by the above measurement, the drive signal related to the one-dimensional light modulation element is corrected, and two-dimensional intensity unevenness and color unevenness, that is, the first direction and the first A process for removing the non-uniformity of the irradiation light distribution in the two directions will be described.

  Hereinafter, the correction process related to the first direction (hereinafter referred to as “vertical correction”) and the correction process related to the second direction (hereinafter referred to as “lateral correction”) will be described.

  First, the vertical correction is required for factors such as variations in the characteristics of the one-dimensional light modulation element, the characteristics of the drive circuit, and the like, and the illumination light becoming non-uniform due to the ambient temperature, changes over time, and the like. That is, if there is no variation in the modulation characteristics of the constituent elements corresponding to each pixel in the one-dimensional light modulation element to be used, and the situation in which the illumination light for the one-dimensional light modulation element is uniform always holds, Ideal image display can be performed by driving control of the element in accordance with the image signal. However, actual one-dimensional light modulation elements have variations in characteristics of the elements themselves due to manufacturing accuracy and the like, variations in characteristics related to the drive circuit of the elements, and the like.

  FIG. 10 illustrates a GLV element as a one-dimensional light modulation element. Each of three fixed ribbons Rs, Rs,... And movable ribbons Rm, Rm,. As a result, one pixel is formed. That is, for the number of pixels necessary for GLV along the ribbon width direction, for example, 1080 pixels, a spatial modulation element is configured by arranging 6480 ribbons along the one-dimensional direction.

  FIG. 5A illustrates a state in which positional variations of the ribbon are generated when no driving voltage is applied. As indicated by “Δh1” and “Δh2” in the figure (the figure shows the amount of deviation in an exaggerated manner), the movable ribbon Rm is deviated from the position where it should originally be located, so that the position (high from the substrate) Variation) is a problem. In other words, when there is no relative displacement between the movable ribbon and the fixed ribbon, when the illumination light is incident on the GLV, the diffracted light is not generated only by regular reflection, so the illuminance on the screen is It becomes the lowest level (for example, black level). However, when diffracted light is generated due to the irregularity of the ribbon position, it is displayed at an unintended brightness level according to the position error of the movable ribbon. If this appears in the form of stripes in the scanning direction (horizontal direction) along with the optical scanning, there is a risk that the contrast of the screen will be lowered.

  FIG. 5B shows a state when a certain drive voltage is applied, and the diffraction grating is formed by moving the movable ribbon relative to the fixed ribbon.

  The position of the movable ribbon group should be essentially the same for the same drive voltage, but in this example, as shown by “ΔH1” and “ΔH2” in the figure, the movable ribbon Rm is displaced (see FIG. Shows the amount of deviation exaggerated.)

  In a configuration in which a GLV in which a plurality of movable ribbons and fixed ribbons are alternately arranged is arranged on a one-dimensional array, the reflective surface of the movable ribbon is moved relative to the reflective surface of the fixed ribbon by controlling voltage application. Therefore, if the irregularity of the ribbon position described above is remarkable, there is a possibility that the brightness and the hue are varied on the screen and the image quality is deteriorated.

  In this example, each of the movable ribbon and the fixed ribbon has a configuration in which the reflecting surface surfaces thereof have a parallel relationship with each other, but each reflecting surface has its reference surface (for example, a GLV element). A structure (so-called blaze-type GLV) arranged in a state inclined at a predetermined angle from a plane parallel to the substrate surface. When the wavelength of incident light is denoted as “λ”, each of the ribbon group arranged in parallel on one plane and the other By operating so that the optical path difference between the ribbons arranged in parallel on one plane is λ / 2, only the + 1st order diffracted light is emitted.) However, variation in ribbon position is also a problem as described above. .

  (B) The ribbon misalignment in the figure has a complicated aspect when variations in manufacturing of the ribbon element itself and variations in characteristics of the drive circuit are further added.

  In addition, when obtaining illumination light to a one-dimensional light modulation element using a laser light source, a uniform brightness intensity distribution (so-called “top hat shape”) in a one-dimensional direction is required as an illumination profile. However, when the lighting conditions are affected by the secular change or the like, the brightness on the screen and the nonuniformity of the color display are caused. For example, even when using a monochromatic light source, it is difficult to obtain uniform illumination light with sufficient accuracy, and it is difficult to always realize uniform illumination conditions for all laser light sources having different wavelengths for each of the three primary colors. is there.

  Therefore, the light intensity is detected considering that the modulation characteristics of the one-dimensional light modulation element and the influence of the illumination profile on the one-dimensional light modulation element are reflected in the intensity of light forming the one-dimensional image. Therefore, measurement is performed using the measuring device 24 as described above. Among the measurement data, the data in the one-dimensional direction corresponding to the major axis direction of the one-dimensional light modulation element represents the luminance and color non-uniformity (deviation from the uniform state) at each pixel position. Can be corrected to remove non-uniformities by measuring in advance or in parallel with image projection.

  The outline of the processing is as follows.

(S1) Measure the display brightness and color non-uniformity. (S2) Calculate the correction data of the drive control related to the one-dimensional light modulation element from the measurement data of (S1). The drive signal correction control for the one-dimensional light modulation element is performed using the data.

  In (S1), for example, each laser light source is sequentially irradiated onto the corresponding one-dimensional light modulation element, and each element (for example, one pixel) constituting each pixel in the one-dimensional light modulation element is used. The ribbon group is supplied with a driving signal (test signal) for displaying a measurement image, and the light intensity of each element is measured. For example, in the case of a GLV element, gradation display can be controlled by changing the drive voltage stepwise from the minimum voltage to the maximum voltage, so that the illumination light is modulated according to the level of each drive voltage (gradation step). You can know the light intensity when.

  Further, in (S2), data that is individually measured according to the difference in pixel position and gradation is data (ideal data or data that should be originally obtained when there is no variation in modulation characteristics). Reference data) and compare. As a result, it is possible to grasp the calculation of the correction data, that is, how much correction should be performed to set the actual light intensity to a predetermined value (or specified value).

  In (S3), the drive signal is actually supplied to the one-dimensional light modulation element to operate by using the calculated correction data.

  In the following, first, the overall influence is measured by the measurement device 24 without distinguishing between the influence on the intensity distribution due to the modulation characteristic of the one-dimensional light modulation element and the influence on the intensity distribution due to the change of the illumination condition or the like. A form when it is assumed that it is reflected in the data will be described.

  An example procedure for intensity distribution measurement is as follows.

(S1-a) Preparation for measurement (position setting of the measuring device 24, etc.)
(S1-b) Turning on the light source (S1-c) Measuring modulation characteristics (S1-d) Turning off the light source (S1-e) Switching to another light source (S1-b), (S1-c), ( Repeat the procedure of S1-d).

  First, in (S1-a), the above-described forms (1) to (3) require the positioning of the movable stage and the attitude control of the movable mirror, etc., but in the form (4), such processing is performed. It is unnecessary.

  In (S1-b), when the laser light source is turned on, the linear beam illuminates the one-dimensional light modulation element corresponding to the light source through the illumination optical system.

  In (S1-c), the modulation characteristics of the constituent elements of each pixel, that is, the luminance characteristics of the modulated light with respect to the drive voltage are measured for all pixel positions related to the one-dimensional light modulation element.

  FIG. 11 is a diagram for explaining the drive signal voltage “DV” applied to the constituent elements of the one-dimensional light modulation element to display the measurement image and the output “PV” of the photosensor constituting the photodetection means 27. FIG. In addition, time “t” is taken on the horizontal axis, “DV” is shown on the vertical axis in FIG. (A), “PV” is shown on the vertical axis in FIG. Shown in relative value.

  In this example, the test signal used for displaying the measurement image is a driving voltage (triangular wave quantized) in which the level (relative value) of DV changes to the right when the DV level is 0, 1,. A driving voltage corresponding to each level is applied to the component to be measured and driven. The intensity of the laser beam thus modulated is measured after being introduced from the projection optical system 9 into the measuring device 24 as described above.

  (A) As shown in the figure, the drive voltage of the test signal is stepped so as to change with a constant increment as time passes, whereas the intensity change of the modulated light does not show a linear characteristic, as shown in the figure. In the low drive voltage range, the intensity is zero, and when the drive voltage exceeds a certain value (threshold value), the intensity does not become zero and increases rapidly.

  Since the measurement of such modulation characteristics is performed in the same manner as described above for each pixel position, a number of data equal to the product of the number of pixels and the number of gradation levels of DV is collected.

  In the above example, the laser light source is switched and the above processing is performed individually. For example, after all the R, G, and B laser light sources are turned on, the wavelength-separated intensity for each color is used. In the configuration form in which measurement is possible, switching of the laser light source is unnecessary and processing time is fast. That is, the transmitted light of each filter is detected by installing the narrow band interference filter which transmits the light of the wavelength of each color separately in the light receiving part of each optical sensor (component of the light detection means 27). As a result, it is possible to simultaneously measure R, G, and B colors.

  In the case of assuming a monochromatic light source, intensity distribution data with the pixel position and gradation level (drive voltage) as variables can be acquired, so that the data is prepared in advance with reference data (ideal values and design target values). By comparison, correction data for element driving can be easily obtained. This is because the degree of excess or deficiency of the drive voltage of each gradation at a certain pixel position can be grasped based on actual distribution data (for example, when the intensity is insufficient, the drive voltage is corrected in a direction to compensate for the deficiency). Just do it.)

  However, in the case of color display, since it is necessary to consider not only the brightness but also the color reproducibility, etc., it is somewhat complicated, and the uniformity that ignores the relationship between colors is insufficient.

  FIG. 12 schematically shows an illumination profile for each color, with the pixel position on the horizontal axis and the optical sensor output (relative value) on the vertical axis.

  When a specific drive voltage (DV) in the test signal is applied to the element and the intensity distribution at each pixel position is measured, “Ic” (c = r, g, b) in the figure indicates the illumination profile (FIG. Is exaggerated in intensity non-uniformity.), “C” is an index for distinguishing the difference in color, and represents one of red (r), green (g), and blue (b). .

  Since the intensity distribution of modulated light is governed by various factors such as variations in modulation characteristics and profile variations due to lighting conditions, it is virtually impossible to perfectly match the intensity distribution of modulated light of each color. This is obvious when considering the influence of environmental changes such as aging and temperature.

  Therefore, correction processing is performed according to the following procedure.

(S2-a) Conversion to luminance value related to modulation characteristic (S2-b) Calculation of maximum white luminance (S2-c) Calculation of target modulation characteristic (S2-d) Calculation of correction data.

  Each illumination profile “Ic” (c = r, g, b) in FIG. 12 is obtained as an output (voltage value) of the optical sensor, and a parameter representing the drive voltage DV is denoted as “v”, and the one-dimensional direction (element When a parameter representing a pixel position in the major axis direction of (x) is written as “x”, it can be expressed by using both functions “Ic (v, x)” (c = r, g, b). For example, based on the data shown in FIG. 11, the characteristic “Ic (v, x1)” when the pixel position x is fixed at a specific position “x = x1” when using a certain laser light source can be obtained. Each “Ic” in FIG. 12 indicates characteristics obtained by changing the pixel position x in the one-dimensional direction when v is fixed to a predetermined value.

  First, in (S2-a), the data (voltage value) represented by Ic (v, x) is converted into a luminance value.

  Specifically, the mixing ratios Rm, Gm, and Bm of the R, G, and B colors are obtained so that the target white light is obtained, and Ic (v, x) is divided by the respective values.

  The tristimulus values of the three primary colors are R (Xr, Yr, Zr), G (Xg, Yg, Zg), and B (Xb, Yb, Zb), and the white tristimulus values are W (Xw, Yw, Zw), the relationship with Rm, Gm, and Bm is defined as follows:

  That is, a vector having white tristimulus values as components is represented by the product of a 3 × 3 matrix having R, G, and B tristimulus values as column vectors and a column vector having a mixture ratio as components. The

  R (Xr, Yr, Zr), G (Xg, Yg, Zg) and B (Xb, Yb, Zb) are determined by the laser light source used, and white also has a color temperature (for example, 6500 K) to (Xw , Yw, Zw) is determined, Rm, Gm, and Bm can be calculated by substituting actual numerical values into the equation [1]. For example, as shown in the following equation, an inverse matrix of the above-described 3 × 3 matrix may be obtained and product operation with a vector having white tristimulus values as components may be performed.

  When the luminance is written as “Y”, the mixing amount for each color laser beam for realizing the luminance of “Y = 1” with respect to white having a predetermined color temperature is calculated.

  Therefore, when the white luminance that can be realized when modulated light is mixed is represented by Ywc (c = r, g, b), the following equation is obtained.

  When the optical sensor used for measuring the light intensity has wavelength sensitivity, or when considering measurement efficiency or the like, the luminance conversion coefficient “Kc” (c = r, g) is used as a correction coefficient in consideration of the influence thereof. , B) is multiplied by the above “Ywc” (c = r, g, b) to obtain the following expression.

  “IYc” (c = r, g, b) indicates, for each light source, white luminance that can be realized when the luminance conversion coefficient is considered.

  FIG. 13 schematically shows IYr, IYg, and IYb with the pixel position (x) on the horizontal axis and the luminance on the vertical axis, and a specific value is not selected as the drive voltage value (v). It is out.

  In this figure, among IYr, IYg, and IYb, since IYb indicates the minimum value “IY0” at a certain pixel position, it can be seen that the maximum white brightness that can be realized is limited by IYb (that is, IYb (Because constraints are imposed on the luminance realization, white luminance larger than IY0 cannot be realized.)

  Here, the v value is fixed, but IYr, IYg, and IYb are functions of v and x (IYc (v, x), where c = r, g, b). A minimum value such as IY0 is searched for the drive voltage value v. As a result, the maximum white luminance (referred to as “IYmax”) is determined in the above (S2-b).

  Next, in (S2-c), a target modulation characteristic, that is, a luminance characteristic with respect to the drive voltage value v (hereinafter referred to as a function “IT (v)” of v) is determined.

  According to the γ characteristic of the image input signal, the ideal modulation characteristic exists in the constituent elements of the one-dimensional light modulation element, and this is expressed by the above-mentioned IT ( v) is “IT (v) = (IYmax) · (IV (v))”.

  FIG. 14 illustrates the target modulation characteristic IT (v), where the horizontal axis represents the drive voltage value v and the vertical axis represents the luminance.

  When the characteristic indicated by IT (v) is called “target modulation characteristic”, for example, the characteristic is examined in advance at the design stage, and a reference table or a calculation formula based on the data is incorporated in the apparatus. A form and a form in which a reference table of data related to the target modulation characteristic, a calculation formula, and the like are incorporated in the apparatus so that the user can specify and select according to the selection of the image signal.

  Next, the correction process (S2-d) performed based on the target modulation characteristic will be described with reference to FIG.

  FIG. 15A shows the IT (v) on the left side of FIG. 15, but the direction of the drive voltage axis is reversed (leftward) so that the vertical axis (brightness axis) has a mirror image relationship with FIG. It is set to. Also, the (B) diagram on the right side shows the modulation characteristics obtained by intensity distribution measurement, with the horizontal drive voltage axis pointing to the right and the vertical axis representing the intensity of the modulated light. As a representative example, the figure shows the characteristic “IYc (v, x)” (c = r, g, b) at each pixel position for the L pixel, the M pixel, and the N pixel.

  The horizontal axis of the target modulation characteristic IT (v) prepared in advance or designated by the user represents the drive voltage value before correction, for example, the luminance with respect to the value indicated by “Vin” in the figure The value of “Y” is determined.

  (B) In the figure, the value on the horizontal axis represents the corrected drive voltage value, and “Vout_l”, “Vout_m”, and “Vout_n” in the figure are drive voltages having the above luminance “Y” as the target luminance. The values are shown for the L pixel, M pixel, and N pixel, respectively. That is, the drive voltage value necessary to obtain the target luminance “Y” generally differs depending on the pixel position, and the component element is driven for each pixel of the one-dimensional light modulation element with the drive voltage value corresponding to each pixel position. There is a need.

  In FIG. 16, the horizontal axis represents the drive voltage axis before correction (corresponding to the horizontal axis in FIG. 15A), and the vertical axis represents the corrected drive voltage axis (in FIG. 15B). This corresponds to the horizontal axis.

  With respect to Vin before correction, Vout_l is calculated for the L pixel, Vout_m is calculated for the M pixel, and Vout_n is calculated for the N pixel.

  As described above, for any Vin indicating the drive voltage value before correction, the corrected data can be calculated by calculating the drive voltage value (Vout_l or the like) determined according to the difference in pixel position. For example, there is a form in which a relationship of correction data corresponding to the pixel position with respect to Vin is obtained and a data table thereof is created. Alternatively, in order to reduce the amount of data and the processing time, not only all correction data corresponding to the drive voltage value and pixel position, but only representative data is stored and estimated by interpolation calculation or the like. Various embodiments such as a form using correction data are possible.

  17 and 18 show an example of a configuration for realizing the vertical correction processing described above. FIG. 17 shows an outline of the configuration, and FIG. 18 shows a main part of the correction calculation configuration.

  In Example 33 shown in FIG. 17, when the video signal VIDEO is input to the signal processing unit 11, the color signals of the three primary colors are output via the internal inverse γ correction circuit, the color space conversion circuit, and the like, and the subsequent data correction unit 34.

  The detection information from the measuring device 24 is sent to the detection signal processing unit 35 and processed by the gain adjustment circuit 35a and the A / D conversion circuit 35b. The gain adjustment circuit 35a is provided for correcting a difference in detection sensitivity of the optical sensor with respect to the detection signal of the modulated light. The A / D conversion circuit 35b converts the gain-adjusted analog signal into a digital signal and sends the data to the measurement data storage unit 34a in the data correction unit 34 for storage. The detection signal processing unit 35 constitutes the light intensity distribution measurement processing unit 14.

  The data correction unit 34 includes a measurement data storage unit 34a, a correction value calculation unit 34b, a data table storage unit 34c, and a selection unit 34d.

  Data measured for the constituent elements of each pixel in the one-dimensional light modulation element is stored in the measurement data storage unit 34a, and the correction value calculation unit 34b performs data for each pixel regarding image display using a test signal for measurement. Is used to obtain the above-described modulation characteristics and derive an illumination profile.

  Then, the correction value calculation unit 34b sends the correction data obtained by performing the processes (S2-a) to (S2-d) to the data table storage unit 34c and stores it in the storage area.

  As described with reference to FIG. 16, the data table storage unit 34 c reads out data stored for correction and outputs a drive signal when a drive signal before correction is received. In this example, the correction data is read with reference to the data table. However, in the mode in which the corrected drive signal is calculated by using an arithmetic process such as an interpolation calculation, the data table storage unit 34c is calculated by an arithmetic processing unit. Replace with.

  The selection unit 34d switches the output from the data table storage unit 34c and the test signal for measurement and sends them to the drive unit 36. That is, the test signal TEST is selected when measuring the intensity distribution, and the output of the data table storage unit 34c is selected when displaying an image.

  The output of the selection unit 34d is sent to a light modulation unit using a GLV element after passing through a D / A conversion circuit 36a and a drive circuit 36b of the next stage constituting the drive unit 36. The D / A conversion circuit 36a is provided for converting the digital signal output from the data correction unit 34 into an analog signal, and the drive circuit 36b uses the converted analog signal as an input signal according to the signal voltage. A drive voltage is supplied to the GLV element.

  The control unit 37 performs control of timing, signal switching, and the like by sending control signals to the respective components such as the signal processing unit 11, the data correction unit 34, the detection signal processing unit 35, and the like. It has functions such as turning on / off and performing optical scanning control when measuring the intensity distribution.

  FIG. 18 shows a configuration example of the correction value calculation unit 34b, which includes the following elements (the numbers in parentheses indicate symbols).

・ Voltage-luminance converter (38)
・ Luminance distribution analysis unit (39)
-Ideal modulation characteristic function generator (40)
・ Multiplier (41)
Correction table generation unit (42)
Data table storage unit (43).

  First, each data of the modulation characteristic “Ic (v, x)” (c = r, g, b) relating to the one-dimensional light modulation element is converted in the voltage-luminance conversion unit 38 as described above, and a function of luminance is obtained. “IYc (v, x)” (c = r, g, b) is obtained. The data of this function is sent to the luminance distribution analysis unit 39 for analysis and sent to the correction table generation unit 42.

  The luminance distribution analyzing unit 39 determines the maximum white luminance IYmax by searching for the minimum value from the data of IYc (v, x) indicating the luminance characteristic, that is, the luminance distribution with respect to the pixel position as described above.

  Also, the ideal modulation characteristic function generation unit 40 generates the data IV (v) and sends it to the multiplication unit 41.

  The multiplying unit 41 multiplies the IV (v) data by the IYmax data from the luminance distribution analyzing unit 39. That is, the data of the target modulation characteristic IT (v) is calculated and sent to each component 42c (c = r, g, b) of the correction table generator 42.

  Based on the data of IT (v) and the data of IYc (v, x) (c = r, g, b), the correction table generation unit 42 generates the drive signal as described with reference to FIGS. Perform correction processing. The data obtained as a result is sent to each component 43c (c = r, g, b) of the data table storage unit 43 and written in a storage area prepared for each color.

  By the measurement and correction processing described above, the luminance profiles related to the laser light sources of the respective colors are aligned at almost the same level, and white of the target color temperature can be correctly expressed.

  In this example, the measurement data obtained by the measurement device 24 is acquired and the correction process is performed without distinguishing the influence on the intensity distribution from the modulation characteristic or illumination profile related to the one-dimensional light modulation element. However, the present invention is not limited to this. It is possible to perform a correction process by measuring the influences of the two separately.

  For example, the intensity distribution is measured in advance with respect to the modulation characteristics related to the constituent elements of the one-dimensional light modulation element under the condition that non-uniformity of the illumination light is excluded. For the illumination profile of the laser light source, the intensity distribution is measured before the image display or while displaying the image. Drive signal correction data can be obtained based on such separate measurement results (that is, in the above example, the influence of both is obtained in one measurement, but two times for each cause. Can be divided into measurements).

  For example, the manufacturing error of the GLV element, the characteristic error of the drive circuit, and the like are less affected by the change over time and the temperature change, whereas the illumination conditions related to the light source are greatly affected by the change over time and the temperature change. In other words, the variation in the modulation characteristics of the GLV element is initially measured once or a small number of times, but the subsequent change is small, whereas the change in the illumination condition takes time or the surrounding environment changes. When it changes, it will be necessary to measure each time.

  Therefore, the process of measuring the modulation characteristics of the element is performed in advance so as to discriminate the influence between the two and not to include the influence of the lighting conditions. Employing a method for measuring an illumination profile is effective in reducing the burden of each correction process and the processing time.

  An example procedure is as follows.

(ST1) Measure the modulation characteristics of the one-dimensional light modulation element (ST2) Measure the illumination profile for the one-dimensional light modulation element (ST3) Correction data based on the measurement data obtained in (ST1) and (ST2) (ST4) At the time of image projection, correction control of the drive signal related to the one-dimensional light modulation element is performed using the correction data of (ST3).

  First, in (ST1), the modulation characteristic when the non-uniformity of the illumination light is eliminated for the constituent elements of the one-dimensional light modulation element is measured.

  For example, using a dedicated device 44 as shown in FIG. 19, the light from the light source unit 45 including the laser light sources (reference light sources) of R, G, and B colors is shaped by the illumination optical system 46 and then reflected by the mirror 47. Then, the one-dimensional light modulation element (GLV element) is irradiated.

  The illumination optical system 46 is provided to irradiate light for each element targeting the constituent elements of each pixel in the GLV element after making the monochromatic laser light from the light source unit 45 into a spot shape.

  Among the constituent elements of the GLV element, the driving voltage according to the test signal as described above is applied to the element to be irradiated with the beam spot, and the light modulated thereby is reflected by the mirror 48 and then used for imaging. The light reaches the light detector 51 through the lens 49 and the spatial filter 50 and is detected. That is, a specific order of diffracted light, for example, first-order diffracted light, is selected by the spatial filter 50 and received by the optical sensor that constitutes the light detection unit 51.

  The GLV element is mounted on a support device 52 for fixing and adjusting the position of the element, and the position of the element and the illumination light at the time of measurement with reference to the alignment mark provided on the GLV element. The setting status is adjusted.

  In the measurement process, the light intensity distribution is measured for each color light source using the pixel position and the drive voltage value as parameters in the same manner as described above, but with high precision uniformity so that the illumination profile does not affect the target element. The target element is irradiated with the intensity distribution.

  The element for which the measurement of (ST1) has been completed is mounted on the image display device, and the measurement data of each element is stored in a storage area in the device and incorporated in the device.

  Next, in (ST2), for example, in the calibration stage immediately before image display, each laser light source in the image display device is turned on to illuminate the one-dimensional light modulation element. Then, a driving voltage according to the test signal is applied to the constituent elements for each pixel, and the modulated light is measured by the measuring device 24 in the same manner as described above.

  Since the data obtained by this measurement includes the influence of the modulation characteristics related to the constituent elements for each pixel, only the nonuniformity of the illumination profile reflecting the influence of only the laser light source and the illumination optical system of the image display device is included. It cannot be measured. This is because when the measurement device 24 measures the light modulated after irradiating the one-dimensional light modulation element mounted on the device, it depends on the modulation characteristic (manufacturing error, characteristic error of the drive circuit, etc.) inherent to the element. This is because there is always an inseparable effect due to the variation in ().

  However, in a situation where the drive voltage to the element is increased to the extent that the influence of the modulation characteristics of the component element can be ignored and the light intensity is increased, it is possible to approximately measure the illumination profile.

  For example, the maximum displacement of the movable ribbon constituting the GLV element is ¼ of the incident light wavelength λ, and 115 nm for blue in which λ = 460 (nm: nanometer). On the other hand, the positional variation on the ribbon surface is about several nanometers, and when moving the movable ribbon with the maximum or close range of displacement, the surface irregularity of the ribbon itself and the error of the drive signal value, etc. The resulting effect is sufficiently small that it can be ignored.

  Therefore, for example, in the drive voltage of the test signal as shown in FIG. 11, a high gradation level range (240 to 255) is adopted, and a large drive voltage is applied to the element to operate, and the modulated light at that time Is measured, it is possible to obtain measurement data of an illumination profile (that is, an intensity distribution according to the pixel position) that sufficiently eliminates the influence of the modulation characteristics of the element. In practice, in the range where the drive voltage is high in the test signal, the intensity change of the modulated light is not so large with respect to the change of the drive voltage (showing a saturated characteristic), so a predetermined drive voltage range is set. By performing intensity measurement, a representative value for each pixel is obtained for the illumination profile.

  In (ST3), the correction data can be calculated in the same manner as described above after integrating the measurement data on the modulation characteristics of the element and the illumination profile. That is, since the influence on the final image (brightness unevenness, color unevenness, etc.) is a combination of both effects, a comprehensive correction process is required.

  An example of the processing procedure is as follows.

(ST3-a) Calculation of illumination profile (ST3-b) Reading of element-specific modulation characteristic data (ST3-c) Calculation of modulation characteristic including illumination profile (ST3-d) Calculation of maximum white luminance and target modulation characteristic (ST3-e) Calculation of correction table.

  First, in (ST3-a), data measured using the measuring device 24 for each one-dimensional light modulation element is obtained. When these are expressed by the function “IQc (v, x)” (c = r, g, b), the maximum value (voltage value) of the light intensity detection data when the element is moved in a large driving voltage range is extracted. At the same time, an illumination profile for each light source is calculated by voltage-luminance conversion (hereinafter referred to as function “Pc (x)” (c = r, g, b)).

  In (ST3-b), data of inherent modulation characteristics (hereinafter referred to as function “ISc (v, x)” (c = r, g, b)) including the element and the drive circuit is obtained. This has been measured in advance as described above for each one-dimensional light modulation element mounted on the image display device.

  Note that (ST3-a) and (ST3-b) may be reversed.

  In (ST3-c), a modulation characteristic “IYc (v, x)” (c = r, g, b) obtained by combining Pc (x) and ISc (v, x) is calculated. Specifically, “IYc (v, x) = Pc (x) · ISc (v, x)” (c = r, g, b) is obtained by multiplication of both.

  In (ST3-d), the calculated IYc (v, x) is analyzed to calculate the maximum white luminance. For example, as shown in FIG. 20, in IYc (v, x) where v is a certain driving voltage value, the area is divided into a plurality of areas along the x direction (pixel arrangement direction), and a white color that can be realized for each area. A maximum value (hereinafter referred to as a function “IYmax (v, x)”) is determined.

  In the above example, IYmax is constant regardless of the pixel position x, but the following maximum luminance function can be obtained.

Region 1 (see “REG1” in the figure): IYmax1 (v, x) = a · x + b
Region 2 (see “REG2” in the figure): IYmax2 (v, x) = c
Region 3 (see “REG3” in the figure): IYmax3 (v, x) = − d · x + e
In the above formula, a, b, c, d, and e are constants, and when the v value is fixed, it is represented by a linear function of x in this example. Higher order functions may be used.

  The target modulation characteristic IT (v, x) is obtained by multiplication of the ideal modulation characteristic IV (v) and IYmax (v, x) as described above.

  In (ST3-e), the drive voltage value corrected from Vin can be obtained from IT (v, x) and IYc (v, x) in the same procedure as described above. In this example, the target modulation characteristic is obtained. Note that the pixel position x has a dependency on. That is, in FIG. 15, correction data is calculated using the target modulation characteristics corresponding to the L, M, and N pixels individually.

  In (ST4), a drive signal to the one-dimensional modulation element is generated from the correction data corresponding to the image input signal, and drive control is performed on the constituent elements for each pixel.

  FIG. 21 shows a configuration example of the correction value calculation unit 34b, and the differences from the configuration example shown in FIG. 18 are as follows.

Data of “IQc (v, x)” (c = r, g, b) is input to the voltage-luminance conversion unit 38 and “Pc (x)” (c = r, g, b) indicating an illumination profile Is output and supplied to the multiplier 53c (c = r, g, b), respectively. The data of “ISc (v, x)” (c = r, g, b) is stored in the storage 54. The data is supplied to the multiplier 53c (c = r, g, b). The output of the multiplier 53c (c = r, g, b) is the luminance distribution analyzer 39 and the correction table generator 42. The luminance distribution analysis unit 39 outputs IYmax (v, x) to the multiplication unit 41, so that the target modulation characteristic IT (v, x) is obtained, and the data according to the target modulation characteristic IT (v, x) is obtained. (C = r, g, b) to be supplied respectively.

  The voltage-luminance conversion unit 39 obtains data (voltage value) having no v dependency by extracting the maximum intensity value from the data of “IQc (v, x)” (c = r, g, b), Data of Pc (x) is output by conversion to a luminance value. A specific conversion method is as described above.

  The multiplier 53c (c = r, g, b) calculates “IYc (v, x) = Pc (x) · ISc (v, x)” (c = r, g, b).

  The luminance distribution analysis unit 39 analyzes IYc (v, x) data and outputs IYmax (v, x), and the multiplication unit 41 calculates a target modulation characteristic as a product of the ideal modulation characteristic IV (v). The

  The correction table generation unit 42 eliminates the luminance and color non-uniformity of the display image based on the obtained target modulation characteristic IT (v, x) and the actually measured modulation characteristic IYc (v, x). As described above, the drive signal is corrected for each color of the illumination light and according to each pixel position. The correction data obtained in this way is written into the storage area of the data table storage unit 43.

  When image display is performed, the image input signal is received and data in the data table storage unit 43c (c = r, g, b) is referred to, and drive control (correction control) according to the pixel position and the drive signal level of the element is performed. ) Is performed.

  In this embodiment, the data relating to the modulation characteristics unique to the element is measured in advance and stored in the storage unit 54, and the measurement data of the illumination profile that is easily affected by changes over time, environmental changes, etc. is measured in a timely manner. The data in the correction table can be updated at any time or as necessary.

  In addition, since IYmax can be set for each region divided in the pixel arrangement direction, it is possible to increase the use efficiency related to luminance (for example, in the case where the value of IYmax is uniformly defined regardless of the pixel position, In particular, there is a possibility that the usable range of luminance cannot be used.)

  Next, the lateral correction process will be described.

  Although the above vertical correction sufficiently guarantees the uniformity of the intensity distribution in the pixel array direction, that is, the long axis direction of the one-dimensional light modulator, a two-dimensional intermediate image formed by optical scanning of the one-dimensional image is projected. When the light passes through the optical system 9, there is a problem that the amount of light at the peripheral part away from the optical axis is reduced.

  For data measured using the measuring device 24 and converted into luminance, it is necessary to consider the position dependency on an axis extending in the direction of optical scanning (hereinafter referred to as “y-axis”). It can be expressed by the function “IYc (v, x, y)” (c = r, g, b).

  For example, in the upper diagram of FIG. 6, in a two-dimensional orthogonal coordinate system in which the x-axis is set on the vertical axis of the display image and the y-axis is set on the horizontal axis, the x-coordinate value and the y-coordinate value are set for a certain drive voltage value v. The measurement data according to can be obtained.

  The graph shown in the lower part of FIG. 6 schematically shows a distribution example (only the right half of the screen) with the y axis on the horizontal axis and the intensity (relative value) on the vertical axis.

  In the state where the v value and the x position are specified, the point P0 in the figure indicates the intensity value at the x position on the vertical line VL0, and the point Pi (i = 1, 2, 3) is VLi (i = 1, 2, 3) The intensity value at the upper x position is shown.

  As shown in the present example, when the measurement image is displayed, the intensity of the wrinkle that ideally shows a uniform distribution gradually decreases as it moves away from y = 0.

  M coordinate values xi (i = 1 to M) on the x axis and N coordinate values yj (j = 1 to N) on the y axis are set, and IYc (v, xi) related to each color is measured. , Yj). As the N value is increased and the measurement interval on the y-axis is reduced, more detailed data on the intensity distribution can be collected. However, if the processing load is increased, the minimum necessary measurement is required. A method of performing data interpolation by setting the number of points is realistic, and it is preferable to linearly interpolate the points P0 and Pi with a straight line or to perform second-order or higher-order interpolation.

  When IYc (v, x, y) data is obtained by measurement, each data is compared with the target value, and the drive signal of the element is corrected so that the intensity distribution is constant. That is, when the value at a certain y position is larger than the target value, the correction data is obtained by reducing the drive voltage value according to the difference between the two. Further, when the value at a certain y position is smaller than the target value, correction data is obtained by increasing the drive voltage value according to the difference between the two.

  However, when the drive voltage is large, the v value cannot be increased beyond the upper limit value, and therefore, the minimum value (luminance value) in the y direction is searched and corrected so as to make it uniform. Note that it is necessary and correction below the lower limit of the v value is impossible. In addition to this, when the maximum white brightness that can be realized has a dependency on the y-coordinate value, it is possible to correct IYmax by extracting the minimum value in the brightness distribution for the y-axis in the same manner as described above. Preferred (multiplying the value calculated by vertical correction by a correction coefficient). The horizontal correction has a slightly complicated aspect in relation to the vertical correction. For example, a form in which the horizontal correction process is performed after the vertical correction process is performed first is possible. That is, if vertical correction is performed at a specific y position (for example, a peripheral position), a measurement image is obtained with a uniform intensity distribution in the x-axis direction in subsequent measurements. If optical scanning is performed in this state and measurement data of modulated light is obtained, data of “IYc (v, y)” having no dependency on the x position can be obtained, and thus lateral correction can be easily performed.

  The correction data obtained as described above is tabulated and stored in a storage area, and is referred to for each optical scanning position corresponding to the y position when an image is displayed, and the element drive signal in the horizontal direction. Is corrected.

  An example of the procedure for lateral correction is as follows.

(S1) The intensity distribution according to the light scanning position is measured. (S2) The drive control correction data related to the one-dimensional light modulation element is calculated using the measurement data of (s1). (S3) At the time of image projection (s2) Using the correction data, the drive signal correction control related to the one-dimensional light modulation element is performed according to the optical scanning position.

  The configuration relating to the lateral correction is included in FIG. 17 already described, and based on the measurement data of the light intensity distribution obtained for each light scanning position, for each scanning position in the second direction (horizontal direction). A drive signal correction process is performed.

  Data necessary for the lateral correction is stored from the detection signal processing unit 35 into the measurement data storage unit 34a of the data correction unit 34, and the correction value calculation unit 34b refers to the data and performs the process (s2). That is, the correction data is written in the storage area of the data table storage unit 34c. At that time, correction data is stored together with information indicating the y position corresponding to the optical scanning position. When displaying an image, the corrected data read from the data table storage unit 34c according to the optical scanning position in response to the output of the signal processing unit 11 is sent from the selection unit 34d to the drive unit 36 for use. Is done. The optical scanning position is always grasped by the control unit 37 at the time of measurement or image display, and a drive signal correction process corresponding to the optical scanning based on timing control is performed.

  FIGS. 22A and 22B are diagrams for conceptually explaining the effect of the above-described correction regarding unevenness in intensity and color unevenness. FIG. 22A shows a front view of a display screen, and FIG. 22B shows an intensity distribution in the vertical direction. , (C) shows the intensity distribution in the horizontal direction.

  When the vertical correction and the horizontal correction are not performed, nonuniformity of the intensity distribution is recognized both in the vertical direction and the horizontal direction of the image as shown by the broken line a in FIG. It is done.

  In the case of only vertical correction, a uniform distribution is realized in the x direction (vertical direction) as indicated by the solid line Cx in FIG. As described above, the vertical correction is a one-dimensional correction in the long axis direction of the light modulation element, and uniformity is recognized in this direction, but non-uniformity is recognized in the horizontal direction of the image.

  When vertical correction and horizontal correction are performed, uniform distribution is realized in the x direction and the y direction as indicated by the solid line Cx in FIG. 5B and the solid line Cy in FIG. As described above, the horizontal correction is correction in a direction corresponding to the optical scanning direction in the two-dimensional intermediate image, and two-dimensional correction can be realized by combining with the vertical correction. As a result, the intensity distribution is made uniform in the horizontal and vertical directions of the image. That is, the data of the above “IYc (v, x, y)” (c = r, g, b) is collected, and the drive signal corresponding to the x position and the y position is corrected with respect to the drive voltage value v of the element. By doing so, luminance unevenness and color unevenness on the display screen can be sufficiently reduced.

  In the above description, the configuration suitable for image display has been centered. However, the scope of application of the present invention is not limited to such a configuration. Therefore, in application to a printer or the like, a two-dimensional image is irradiated onto a recording medium. Design may be performed in accordance with the purpose and specifications of the device such as transfer.

  Since the basic matters have been described in the following examples, the configuration for measuring the light intensity will be mainly described with reference to FIGS.

  FIG. 23 schematically shows an appearance example of the image display device (projector) 55. In this example, the above-described form (2) is adopted, and the measurement device 24 is mounted on a movable stage.

  The measurement device 24 and the table 56 that is moved by mounting the device (excluding the Fresnel lens) are provided on the front surface of the device housing 55a. For example, the support portion of the table 56 is fixed to the base frame 55b using a mounting member 57 (attachment or the like). And about the table 56, as shown by the continuous line at the time of image projection, the measuring apparatus 24 is positioned in the place away from the opening part 9a of the projection optical system 9. FIG. Moreover, at the time of intensity | strength measurement, as shown with a dashed-two dotted line, the measuring apparatus 24 is prescribed | regulated in the position which covers the opening part 9a.

  As described above, it is effective to improve the accuracy and the like to perform the intensity distribution measurement at a position closest to the projected image on the screen.

  The measuring device 24 is provided with a condensing Fresnel lens and an integrating sphere, and an integrating sphere entrance port is set at a position where an image emitted from the projection lens is formed by the Fresnel lens.

  As shown in FIG. 24, the Fresnel lens 58 has a concentric Fresnel zone 58a formed on a transparent substrate (acrylic plate or the like). For example, the effective diameter is about 150 mm and the thickness is about 1.5 mm. . The Fresnel lens 58 is detachably supported on a support base (61) described later.

  Further, as shown in FIG. 25, the integrating sphere 59 is formed with a slit-like incident port 59a that is elongated in the vertical direction corresponding to the longitudinal direction of the one-dimensional image. A detection port 59b is formed. For example, the inner diameter of the integrating sphere 59 is 100 mm, and the opening size of the incident port 59a is 34 mm in length and 7 mm in width. The light detection port 59b is a circular hole, and the opening size is 10 mm in diameter.

  The moving direction of the table 56 on which the measuring device 24 is mounted corresponds to the direction of optical scanning, and a driving mechanism is provided for moving the table 56 along the lateral direction according to the rotation of the galvanometer mirror.

  26 to 28 show an outline of an example of the drive mechanism 60. FIG. 26 is a front view, FIG. 27 is a side view, and FIG. 28 is a perspective view of the main part.

  As shown in FIGS. 26 and 27, in this example, positioning control of the table 56 is performed by a linear moving means using a feed screw, a guided member, a guide rail, a motor and the like.

  A support base 61 of the drive mechanism 60 is attached to the base frame 55b using an attachment 62, and the support base 61 is rotated by a motor (such as a DC motor) that constitutes a drive source 63 and the motor. A feed screw 64 is disposed, and the feed screw 64 is coupled to the motor shaft using a coupling member 64c.

  The feed screw 64 is rotated by the motor, and the table 56 fixed to the guided member 65 is guided and moved along the guide rails 61g and 61g (see FIG. 28). For example, as shown by a solid line in FIG. 26, the measuring device 24 is moved to a measurement position in a state of covering the opening 9a of the projection optical system 9, and at the time of image projection, as shown by a two-dot chain line in FIG. The measuring device 24 is moved to the retracted position so as not to block the projection light.

  When controlling the positioning of the table 56 using such a linear guide mechanism, an absolute position detecting means such as an encoder is provided so that the position (lateral position) in the moving direction of the table 56 can be detected. It is preferable to configure. Thereby, the shift | offset | difference etc. of a horizontal position with respect to a projection lens are correctable. Note that a configuration in which the table is moved over a predetermined range in the moving direction by detecting the on / off state of the optical sensor or the like may be employed. In this case, the reference position of the table is determined. Thus, the measuring device can be moved in the horizontal direction of the image, and the mechanism is simplified.

  The integrating sphere 59 and the light detection unit 66 are mounted and fixed on the table 56, and the Fresnel lens 58 is positioned between the housing 55b and the integrating sphere 59 as shown in FIG. In addition, a light detection unit 66 is attached to the side of the integrating sphere 59, and the light detection unit incorporates detection means using a photodiode or the like. The support base 61 is provided with a mounting mechanism for inserting and removing the Fresnel lens 58, and this mechanism is independent of a positioning mechanism for moving the integrating sphere 59 and the like.

  As for the photosensors constituting the photodetecting section 66, it is possible to use a common detection element for each of the colors R, G, and B. However, as shown in FIGS. 29A and 29B, there are three systems. It is preferable to provide the detection means. That is, the red sensor 67R, the green sensor 67G, and the blue sensor 67B are arranged, and the filters 68R, 68G, and 68B having wavelength selectivity for each color are provided on the light receiving surface of each sensor unit.

  As the filter, it is preferable to use a narrow-band interference filter that selectively transmits only light of three colors of laser light wavelengths, and the light transmitted through the filter is detected by the sensor unit and converted into an electrical signal. The wavelength width of each color laser beam is within a maximum of 10 nm and is sufficiently narrow, and the wavelengths of each color of R, G, and B are sufficiently separated from each other. The light intensity distributions of the three colors can be measured simultaneously and independently without interfering with each other, which contributes to shortening of the measurement time.

  In FIG. 26 and FIG. 27, a cover member for reducing the influence of external light by covering the periphery of the Fresnel lens 58, the integrating sphere 59, and the like is omitted. For example, as shown in FIG. A configuration in which the Fresnel lens 58 is disposed in a square box-shaped hood 69 having an opening at one end and the integrating sphere 59 and the like are covered using covers 70 and 70 attached to the back of the hood is preferable.

  As described above, at the time of measurement, the measuring device 24 is positioned immediately after the projection optical system 9, and the light emitted from the projection optical system 9 is introduced into the integrating sphere 59 via the Fresnel lens 58 without leaking outside. The portion including the measuring device 24 and its driving mechanism 60 can be used for protecting the projection optical system 9. That is, when the image display device is not operated or not used, the measurement device 24 is held at the above measurement position, thereby providing a cover or hood function for the projection lens, etc. It is possible to prevent dust or dirt from being deposited. It is also effective as a safety measure against laser light. For example, it is possible to prevent spectators and workers from inadvertently looking into the projection lens, and to take measures to prevent harm to the human body. it can.

  In this embodiment, the table 56 to be moved and its driving mechanism are used to move the measuring device 24 to the measurement position immediately after the projection optical system 9 or to follow the change in the optical scanning position according to the control of the galvanometer mirror. Therefore, since the position of the measuring device can be controlled, and the measuring device 24 can be moved to the retracted position during image projection, the configuration is simple and the positioning can be easily controlled.

  The moving means and method of the measuring apparatus are not limited to this example, and various configurations using a linear motor or the like are possible. Further, in this example, the configuration using the attachment for attachment is shown so that the measuring means (measuring unit) including the measuring device 24 and the moving mechanism can be attached to and detached from the device casing. A configuration form in which the measuring means is fixed to the apparatus housing or integrated is possible.

  In the above embodiment, the configuration in which the Fresnel lens is mounted on the support base and the integrating sphere and the light detection unit are mounted on the table and moved is shown. As described above, in the configuration using the two moving tables 56A and 56B, the integrating sphere 59 and the like are mounted on one moving table 56A, and the Fresnel lens 58 and the moving table 56A are installed on the moving table 56B. Absent.

  In FIG. 30A, the measurement device 24 is in a retracted position so that an image can be projected onto the front screen and the light path is not blocked by the integrating sphere 59 on the front surface of the main body of the image display device 55A. Have come to. In FIG. 30B, the Fresnel lens 58, the integrating sphere 59, and the like are positioned in front of the projection optical system of the image display device 55A by moving the moving table 56B, and the intensity distribution measurement is performed. Is called.

  FIG. 31 is a diagram for explaining switching of measurement lines in accordance with the position control of the movement table 56A. In the state shown in FIGS. (A) to (C), the position of the movement table 56B is fixed, and the movement table 56A. Only move.

  FIG. 31A shows a state in which the moving table 56A on which the integrating sphere 59 is placed is at a position close to the upper side of the figure, and FIG. 31B shows an image display device. The moving table 56A is positioned so that the projection lens 55A (not shown), the Fresnel lens 58, and the integrating sphere 59 are positioned on a straight line. FIG. 31C shows a state in which the moving table 56A on which the integrating sphere 59 is placed is at a position close to the lower side of the figure.

  In the state shown in FIGS. (A) and (C), the integrating sphere 59 has an offset in the horizontal direction, and the measurement device 24 sets the measurement lines (for example, VL3 and VL0 in FIG. The intensity distribution is measured at a vertical line located on the opposite side of VL3. In the state shown in FIG. 6B, the intensity distribution is measured by the measuring device 24 in the central measurement line (for example, see VL0 in FIG. 6) related to the projection image.

  In this configuration, when acquiring two-dimensional measurement data regarding the intensity distribution, the integrating sphere 59 is moved in the horizontal direction by the moving table 56A while the position of the Fresnel lens 58 is fixed.

  Using the measurement means described above, it is possible to measure the intensity including the lateral direction following the galvanometer mirror angle (swing angle) to obtain a profile, and in the display image by two-dimensional correction including the vertical correction and horizontal correction. It is possible to achieve high image quality by sufficiently eliminating luminance unevenness and color unevenness.

  This is sufficiently effective in a single projector apparatus, but is a type in which projection images from a plurality of projector apparatuses are arranged in a horizontal direction or a vertical direction to project an image on one large screen (so-called type). In the ring), it is effective to realize a uniform image display.

  For example, in the example shown in FIG. 32, images are projected on a horizontally long screen by projecting the respective images GA, GB, GC in the horizontal direction using three projector devices 55A, 55B, 55C. Yes.

  At this time, if the intensity distributions related to the images of each device are uneven and have large variations, a “seam problem” occurs at the boundary between adjacent images. For example, when the central part of each image (patch image) has a light distribution tendency and the peripheral part has a dark distribution tendency, when such images are connected, the joint part becomes dark. That is, with respect to the projection image by each device, it is required to reduce luminance unevenness and color unevenness as much as possible in the vertical direction and the horizontal direction.

  And it is necessary to unify intensity | strength between apparatuses so that a difference may not arise regarding the intensity distribution between each image.

  For example, communication devices are provided between devices that project adjacent images so that light intensity distribution data at the periphery of each image can be exchanged, and the light intensity distributions match at the joints between adjacent images. Thus, it is preferable to mutually correct the brightness, color level, and the like. This makes it possible to make the joints inconspicuous and display a uniform large screen image.

  In addition, about the communication form between apparatuses, the wire type using an electrical connection member may be sufficient, and infrared communication and a radio | wireless type may be sufficient.

  In addition, the above-described configuration is also effective in a format (so-called stacking) in which projection images from a plurality of devices are displayed in the same place. For example, when such images are superimposed when the central part of each image is bright and the peripheral part has a dark distribution tendency, the contrast difference between the central part and the peripheral part becomes conspicuous. That is, for each projection image, it is required to reduce luminance unevenness and color unevenness as much as possible in the vertical direction and the horizontal direction. For this purpose, two-dimensional correction including the vertical correction and horizontal correction is effective.

  According to the configuration described above, for example, the following advantages can be obtained.

  -With respect to the two-dimensional light intensity distribution of the image projected on the screen, data including brightness unevenness and color unevenness is measured, and light modulation element drive correction is performed based on the measurement data. It is possible to improve. In other words, in the image by the light transmitted through the projection lens after the optical scanning, a decrease in the amount of peripheral light is a problem, but it has a two-dimensionally uniform brightness by correcting the drive signal of the light modulation element, In addition, image display without color unevenness can be realized.

  ・ Measures to reduce the amount of ambient light due to the projection lens can be taken by the above-described measurement and correction processing, so that the specification requirements for the projection lens (suppression of a decrease in the amount of ambient light) can be alleviated. Therefore, it is not necessary to use an expensive projection lens, which contributes to cost reduction.

  -As a measure against lateral shift of the projection lens, etc., by providing a mechanism for moving the measuring device in the lateral direction, it is possible to measure and correct changes in the peripheral light amount ratio.

  ・ When a light diffusing means (diffuser) is installed at the position of a two-dimensional intermediate image formed after optical scanning, there is a problem with the optical effect due to dust or dirt adhering to it. Since it is detected by being reflected in the distribution measurement data, color unevenness and brightness unevenness caused by dust etc. can be removed by correction.

  -By providing a light intensity distribution measuring device with a protective function as a projection lens hood, it is possible to prevent dust from adhering to the projection lens and to protect the projection lens from scratches. In addition, it is possible to prevent damage to the eyes and the like due to laser light by providing the measuring device with a safety function that prevents the projection lens from looking into the inside.

  -It is effective in the structure form which displays one image combining each projection image by several projectors. For example, when a single screen is formed by arranging the images along a predetermined direction, a large screen image can be displayed without causing the observer to feel a joint by minimizing the decrease in the amount of light around the images.

It is a figure which shows the structural example of the image generation apparatus which concerns on this invention. It is explanatory drawing of the image signal for a measurement. It is a figure which shows the principal part about the structural example of the optical system of an image generation apparatus with FIG. It is a figure for demonstrating the relationship between an optical scanning position and a movable stage position. It is the figure which illustrated the opening formed in the integrating sphere. It is explanatory drawing of intensity distribution in the horizontal direction (horizontal direction) of a two-dimensional image. It is a figure for demonstrating the relationship between an optical scanning position and the setting position of a measuring apparatus about a different configuration form from FIG. It is a figure which shows the structural example which has arrange | positioned the movable mirror in the back | latter stage of a projection optical system. It is a figure which shows the structural example which has arrange | positioned the partial reflection mirror in the back | latter stage of a projection optical system. It is explanatory drawing regarding the operation principle of a GLV element, and the variation in a ribbon position. It is a figure for demonstrating the drive voltage change of a test signal, and an optical sensor output. It is a figure which shows the illumination profile for every color roughly. It is explanatory drawing of luminance distribution and its minimum value IYO. It is the graph which illustrated ideal modulation characteristic IT (v). It is explanatory drawing of the correction process on the basis of a target modulation characteristic. It is explanatory drawing of the correction table produced | generated for every pixel. FIG. 18 shows a configuration example related to the correction processing, and FIG. 18 is a diagram showing an outline. It is a figure which shows the principal part of a correction | amendment calculation structure. It is a figure which shows the example of an apparatus used for the measurement of the modulation characteristic of a GLV element. It is explanatory drawing of the example which determines the maximum white value which can be implement | achieved about each area | region of luminance distribution. It is the figure which showed the structural example of the correction value calculating part. It is a system diagram which shows the structural example of an image generation apparatus. FIG. 24 to FIG. 29 show an example of an embodiment according to the present invention, and this figure is a schematic view showing the appearance of the apparatus. It is the figure which illustrated the Fresnel lens. It is the figure which illustrated the integrating sphere. It is a figure for demonstrating the moving mechanism of a measuring apparatus with FIG. 27, FIG. 28, and this figure is the schematic of the apparatus seen from the front. It is the schematic which shows the principal part of the apparatus seen from the side. It is the perspective view which illustrated the linear movement mechanism of the table which mounted the measuring device. It is explanatory drawing of the photodetection means using the narrowband interference filter for every color. FIG. 31 shows a configuration example including two movement tables together with FIG. 31. This figure is a schematic plan view showing an image projection state in FIG. (A) and a measurement state in FIG. It is a schematic plan view which shows a mode that the position of an integrating sphere is changed in the state to which the position of the Fresnel lens was fixed to (A) thru | or (C). It is explanatory drawing of the form which performs the image display (tiling) which synthesize | combined several images using three projector apparatuses.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Image generation apparatus, 4R, 4G, 4B ... One-dimensional light modulation element, 6 ... Spatial filter, 9 ... Projection optical system, 13 ... Driving means, 15 ... Light intensity distribution measurement means, 18 ... Optical scanning means, 20 ... Correction means, 24 ... measuring device, 25 ... optical element, 26 ... integrating sphere, 27 ... light detecting means, 28, 29 ... moving means, 30 ... movable optical element, 32 ... optical element, 59 ... integrating sphere, 68R , 68G, 68B ... Filter

Claims (14)

One-dimensional light modulation element and its driving means, optical scanning means for scanning a one-dimensional image obtained by modulating light using the one-dimensional light modulation element, and a two-dimensional intermediate image obtained by the optical scanning means In an image generation apparatus provided with a projection optical system for projecting
When the light intensity measurement image is displayed by the control of the driving means, the light emitted from the projection optical system is received, the first direction corresponding to the long axis direction of the one-dimensional light modulation element, and the A light intensity distribution measuring means for measuring an intensity distribution in a second direction orthogonal to the direction;
The light intensity in the first direction and the second direction is made uniform by correcting the drive signal related to the one-dimensional light modulation element based on the measurement data from the light intensity distribution measuring means and controlling the drive means. An image generating apparatus characterized by comprising correction means for converting the image into a corrective manner. The image generation apparatus according to claim 1,
An image generating apparatus characterized in that the measurement image is output as the entire two-dimensional intermediate image and measured by the light intensity distribution measuring means in a preliminary stage of performing projection for image display. The image generation apparatus according to claim 1,
The image generation apparatus characterized in that the measurement image is incorporated into a part of the two-dimensional intermediate image, output, and measured by the light intensity distribution measuring means. The image generation apparatus according to claim 1,
The image generation apparatus, wherein the light intensity distribution measuring unit detects an averaged light intensity after condensing the light emitted from the projection optical system. The image generation apparatus according to claim 4,
The light intensity distribution measuring means is for detecting the light intensity averaged by the integrating sphere, an optical element for condensing the light emitted from the projection optical system and introducing it into the integrating sphere, and the integrating sphere. An image generation apparatus comprising: a light detection unit. The image generation apparatus according to claim 1,
When measuring the light intensity distribution for the light emitted from the projection optical system, the optical scanning means is controlled to change the light scanning position in the second direction, and the light intensity distribution is measured for each light scanning position. An image generation apparatus characterized by sending data to the correction means. The image generation apparatus according to claim 6,
The image generation apparatus, wherein the correction unit corrects the drive signal in accordance with the light scanning position in the second direction based on the measurement data of the light intensity distribution obtained for each light scanning position. The image generation apparatus according to claim 1,
A measuring device constituting the light intensity distribution measuring means and a moving means thereof are provided, and the measuring device is moved to a position near the projection optical system at the time of measuring the light intensity distribution, and the emitted light of the projection optical system is measured. An image generation apparatus characterized by being introduced into the apparatus and moving the measurement apparatus to a position that does not affect display during image projection. The image generation apparatus according to claim 8,
An image generating apparatus characterized in that, when measuring the light intensity distribution with respect to the light emitted from the projection optical system, position control of the measuring apparatus is performed in accordance with the optical scanning position in the second direction. The image generation apparatus according to claim 1,
A measuring device that constitutes the light intensity distribution measuring means is fixedly installed, and a movable type for introducing light into the measuring device by changing the optical path of the emitted light of the projection optical system when measuring the light intensity distribution An image generation apparatus comprising the optical element. The image generation apparatus according to claim 1,
An optical element for introducing a part of the light emitted from the projection optical system into the measuring device when performing image projection while fixedly installing the measuring device constituting the light intensity distribution measuring means. An image generation apparatus characterized by being provided. The image generation apparatus according to claim 1,
Equipped with a plurality of light sources with different wavelengths and one-dimensional light modulation elements corresponding to each light source,
The light detection means constituting the light intensity distribution measurement means includes a filter that transmits only light having a wavelength corresponding to each light source, and a light sensor that receives light transmitted through the filter. An image generating device. The image generation apparatus according to claim 8,
An image generating apparatus, wherein the projection optical system is protected by positioning the measuring device in the vicinity of the projection optical system when image projection is not performed or the apparatus is not operated. The image generation apparatus according to claim 1,
The diffracted light of a specific order that has been modulated by the one-dimensional light modulation element and then selected by a spatial filter is projected onto a screen via the light scanning means and the projection optical system, and image display is performed. An image generating device.

Images