JP2006259242A - Optical equipment and adjusting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide optical equipment capable of displaying an image with less distortion by using a display device using a one-dimensional display element, and an adjusting method. <P>SOLUTION: A secondary optical system 34-1 generates parallel beams by collimating light made incident from a one-dimensional modulation part 32 through a schlieren optical system 33, and makes the generated parallel beams incident on a scanning mirror 55. The scanning mirror 55 reflects the light made incident from the secondary optical system 34-1, and makes it incident on a secondary optical system 34-2. The secondary optical system 34-2 condenses the light made incident from the scanning mirror 55 and forms a two-dimensional image. A shim 36 is inserted between a base 31 and a scanning part 35, the scanning mirror 55 is turned with a line parallel with a line B1 as an axis, and the incident angle of the light made incident on the scanning mirror 55 from the secondary optical system 34-1 is adjusted. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an optical apparatus and an adjustment method, and more particularly, to an optical apparatus and an adjustment method that can display an image with less distortion using a one-dimensional display element.

  In recent years, the introduction of a new broadcasting system, the improvement of image processing speed accompanying the advancement of arithmetic elements, or the form using digital signal processing (digital cinema) from the conventional form (so-called analog cinema) that performs enlarged projection using film. ), The demand for high resolution is increasing. A two-dimensional display element such as a liquid crystal light valve is in a situation where it is difficult to follow the trend toward higher resolution, and this is due to inconveniences due to an increase in the number of pixels and a reduction in pixel size. It is done.

  For example, if an attempt is made to increase the resolution by increasing the (total) number of pixels while keeping the size of the display element fixed, the aperture of the display unit is forced to be reduced, resulting in a sacrifice in brightness. (It becomes difficult to realize a bright projector device). On the other hand, trying to achieve high resolution with a fixed pixel size inevitably incurs the disadvantage of increasing the size of the display element, which increases the size of the device including the optical system and makes it expensive. turn into.

  Note that the reduction in the size of the pixels necessitates taking measures to prevent a smaller amount of foreign matter from being mixed in the display element manufacturing process. In addition, in order to increase the size of the display element, it is necessary to increase the size of the production apparatus itself.

  In this regard, if a configuration in which scanning is performed in a predetermined direction using a one-dimensional display element is employed, the number of pixel arrays of elements can be greatly reduced.

  As an example, when a two-dimensional display element is used in a high-definition television or a high-definition television, so-called HDTV (High Definition TeleVision), the number of elements corresponding to 1920 × 1080≈2,070,000 pixels is required. In a system that scans in the H (horizontal) direction using a one-dimensional display element, the latter advantage is obvious because it can be realized with the number of elements corresponding to 1080 pixels.

  In view of this, there has been proposed a technique for achieving a higher resolution by using a one-dimensional display element. As a display device that displays an image using such a one-dimensional display element, for example, a linear beam (linear light) is applied to a one-dimensional light modulation element arranged in one direction as a one-dimensional display element. ) And the light obtained by spatially modulating the linear beam in the one-dimensional light modulation element is scanned along a direction orthogonal to the arrangement direction of the one-dimensional light modulation element using a galvano mirror. However, a method for displaying an image by projecting it on a screen has been proposed (see, for example, Patent Document 1).

JP 2004-4256 A

  By the way, by using a plurality of display devices that display images on the screen, images displayed by the respective display devices are arranged in a predetermined direction, or a plurality of images are superimposed to display one image. A larger image or a larger amount of light can be displayed on the screen.

  In this case, if the image displayed on the screen by each display device is distorted, it is impossible to arrange the images so that the border between adjacent images is not conspicuous on the screen or to superimpose the images accurately. End up.

  For example, when a display device using a two-dimensional display element such as a liquid crystal panel or DMD (Digital Micro mirror Device) (trademark) is used, distortion of an image displayed on the screen as shown in FIG. This is caused by the tilt of the display device with respect to the screen. In FIG. 1A, the image displayed on the screen is displayed in a state tilted in the clockwise direction in the drawing. Therefore, by tilting the display device itself (adjusting the angle) with respect to the screen and rearranging the display device, distortion of the image on the screen can be corrected as shown in FIG. 1B. In FIG. 1B, the left and right edge sides in the image are parallel to the vertical direction, and the upper and lower edge sides in the image are parallel to the horizontal direction, and a rectangular image without distortion is displayed. ing.

  On the other hand, for example, when a display device using a one-dimensional display element constituted by GLV (Grating Light Valve) (trademark) or the like is used, for example, as shown in FIG. The one-dimensional image 11-1 (light for forming an image) that is obtained by modulation and is long in the vertical direction in the figure is scanned from the left side to the right side in the figure by, for example, a galvanometer mirror. And projected onto the screen. At this time, if the light source or the one-dimensional light modulation element is tilted with respect to the galvanometer mirror, or if the image is tilted due to a deviation of the optical axis of the imaging optical system composed of a lens or the like, as shown in FIG. 2B. The one-dimensional image 11-2 incident on the galvanometer mirror is inclined not parallel to the vertical direction. The one-dimensional image 11-2 incident on the galvanometer mirror is scanned from the left side to the right side in the figure and projected onto the screen by the galvanometer mirror while being tilted.

  Therefore, as shown in FIG. 3A, since the one-dimensional image with the galvanometer mirror tilted is scanned from the left side to the right side and from the right side to the left side, the two-dimensional image formed thereby is parallel. The two-dimensional image is projected on the screen as it is, and a distorted image of the parallelogram is displayed on the screen as shown in FIG. 3B.

  Image distortion caused by the tilt of the light source or the one-dimensional light modulation element with respect to the galvanometer mirror or the tilt of the image due to the deviation of the optical axis of the imaging optical system causes the projected image itself to be distorted. It cannot be corrected by reworking. In the above-described technique, an image cannot be displayed without causing such distortion using a display device using a one-dimensional display element.

  For this reason, in a display device using a one-dimensional display element, the superimposed images are shifted on the screen, and the colors of the images displayed on the screen appear to be shifted, or between adjacent images. As a result, there was a gap in the image, and the images could not be accurately arranged or superimposed on the screen.

  The present invention has been made in view of such a situation, and makes it possible to display an image with less distortion using a display device using a one-dimensional display element.

  The optical apparatus of the present invention is reflected on the reflecting surface by rotating the reflecting surface of the reflecting means for reflecting the light for forming the first image, which is a parallel light beam, about the predetermined first straight line. Adjusting means for adjusting the angle of the light for forming the first image with respect to the second straight line perpendicular to the traveling direction of the light for forming the first image, and parallel rays reflected by the reflecting means Scanning in the direction parallel to the third straight line perpendicular to the traveling direction of the light for forming the first image and perpendicular to the second straight line. Imaging means for condensing the light for forming the first image and forming a second image composed of the scanned first image on the first plane perpendicular to the optical axis It is characterized by providing.

  The adjustment means can adjust the angle of the light for forming the first image incident on the reflection surface of the galvanometer mirror as the reflection means with respect to the second straight line.

  The optical device collimates the incident light, generates light for forming a first image that is a parallel light beam, and causes the light for forming the generated first image to enter the reflecting means. A collimation means can further be provided.

  In the adjustment method of the present invention, the light for forming the first image, which is a parallel light beam scanned in a direction parallel to the first straight line perpendicular to the traveling direction of the light for forming the first image, is used. A first image that is a parallel light beam is formed on an imaging unit that focuses and forms a second image composed of the scanned first image on a first plane perpendicular to the optical axis. Light for reflecting the light for reflection on the reflecting surface of the reflecting means and making it incident, and light for forming the first image by rotating the reflecting surface of the reflecting means about the predetermined second straight line Adjusting the angle of light for forming the first image reflected on the reflecting surface with respect to the third straight line perpendicular to the traveling direction of the first straight line and perpendicular to the first straight line. .

  In the optical apparatus of the present invention, the reflecting surface of the reflecting means for reflecting the light for forming the first image that is a parallel light beam is rotated about the predetermined first straight line and reflected on the reflecting surface. The parallel light beam reflected by the reflecting means is adjusted with respect to the second straight line perpendicular to the traveling direction of the light beam for forming the first image of the light beam for forming the first image. Light for forming a first image, scanned in a direction perpendicular to the traveling direction of the light for forming the first image and parallel to a third straight line perpendicular to the second straight line The light for forming the first image is collected, and a second image composed of the scanned first image is formed on the first plane perpendicular to the optical axis.

  In the adjustment method of the present invention, the light for forming the first image, which is a parallel light beam scanned in the direction parallel to the first straight line perpendicular to the traveling direction of the light for forming the first image. The first image, which is a parallel light beam, is formed on the imaging means that forms a second image consisting of the scanned first image on the first plane perpendicular to the optical axis. The light to be reflected is reflected on the reflecting surface of the reflecting means, and the incident reflecting step and the reflecting surface of the reflecting means are rotated about a predetermined second straight line to form the first image. The angle of the light for forming the first image reflected on the reflecting surface with respect to the third straight line perpendicular to the light traveling direction and perpendicular to the first straight line is adjusted.

  According to the present invention, an image can be displayed. In particular, an image with less distortion can be displayed using a display device using a one-dimensional display element.

  Embodiments of the present invention will be described below. The correspondence relationship between the invention described in this specification and the embodiments of the invention is exemplified as follows. This description is intended to confirm that the embodiments supporting the invention described in this specification are described in this specification. Therefore, although there is an embodiment which is described in the embodiment of the invention but is not described here as corresponding to the invention, it means that the embodiment is not It does not mean that it does not correspond to the invention. Conversely, even if an embodiment is described herein as corresponding to an invention, that means that the embodiment does not correspond to an invention other than the invention. Absent.

  Further, this description does not mean all the inventions described in this specification. In other words, this description is for the invention described in the present specification, which is not claimed in this application, that is, for the invention that will be applied for in the future or that will appear and be added by amendment. It does not deny existence.

  The optical apparatus according to claim 1 is configured such that the reflecting surface of the reflecting means (for example, the scanning unit 35 in FIG. 4) that reflects the light for forming the first image that is a parallel light beam has a predetermined first straight line. (For example, a straight line parallel to the straight line B1 in FIG. 4), the light for forming the first image reflected by the reflecting surface is rotated. Adjustment means (for example, shim 36 in FIG. 4) for adjusting an angle with respect to a second straight line (for example, a straight line parallel to the z-axis direction in FIG. 4) perpendicular to the traveling direction, and parallel light rays reflected by the reflection means Light for forming a certain first image, which is perpendicular to the traveling direction of the light for forming the first image and perpendicular to the second straight line (for example, x in FIG. 4). The light for forming the first image scanned in a direction parallel to the straight line parallel to the axial direction is collected and perpendicular to the optical axis. Imaging means (for example, the secondary optical system 34-2 in FIG. 4) that forms a second image composed of the scanned first image on one plane (for example, the image plane 121 in FIG. 7). It is characterized by providing.

  In the optical apparatus according to claim 2, the adjusting unit (for example, shim 36 in FIG. 4) causes the first image incident on the reflecting surface of the galvanometer mirror (for example, the scanning unit 35 in FIG. 4) as the reflecting unit. The angle with respect to the 2nd straight line of the light for forming is adjusted, It is characterized by the above-mentioned.

  The optical apparatus according to claim 3 collimates the incident light, generates light for forming a first image that is a parallel light beam, and reflects the light for forming the generated first image. A collimating means (for example, the secondary optical system 34-1 in FIG. 4) for entering the means (for example, the scanning unit 35 in FIG. 4) is further provided.

  The adjustment method according to claim 4 scans in a direction parallel to a first straight line (for example, a straight line parallel to the x-axis direction in FIG. 4) perpendicular to the traveling direction of light for forming the first image. The light for forming the first image, which is a parallel light beam, is collected and scanned on the first plane perpendicular to the optical axis (for example, the image plane 121 in FIG. 7). Reflecting means (for example, the light for forming the first image, which is a parallel light beam), is formed on the image forming means (for example, the secondary optical system 34-2 in FIG. 4) that forms a second image consisting of images. The reflection step (for example, the process of step S13 in FIG. 18) that is reflected and incident on the reflection surface of the scanning unit 35 in FIG. 4 and the reflection surface of the reflection means are set to a predetermined second straight line (for example, in FIG. 4). (A straight line parallel to the straight line B1) as an axis, and is perpendicular to the traveling direction of the light for forming the first image and the first straight line An adjustment step for adjusting the angle of the light for forming the first image reflected on the reflecting surface with respect to a third straight line perpendicular to (for example, a straight line parallel to the z-axis direction in FIG. 4) (for example, FIG. 18 step S15).

  The present invention forms an image output device such as a printer, an image reading device such as a scanner, and a one-dimensional image obtained by modulating light with a one-dimensional light modulation element by scanning with a scanning unit. It can be applied to a front projection type or rear projection type display device that projects and displays this.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 4 is a perspective view showing a configuration example of a display device to which the present invention is applied. In the drawing, the x axis, the y axis, and the z axis represent axes of a coordinate system orthogonal to each other, and the arrow A1 represents the direction in which the scanning mirror 55 is rotated. The straight line B1 is a straight line on the xy plane where the angle between the x-axis and the y-axis and the straight line B1 is 45 degrees, and the scanning unit 35 is rotated to adjust the position of the scanning mirror 55. It represents a straight line parallel to the axis.

  The display device includes a base 31, a one-dimensional modulation unit 32, a schlieren optical system 33, a secondary optical system 34-1, a secondary optical system 34-2, a scanning unit 35, and a shim 36. On the substrate 31, a one-dimensional modulation unit 32, a schlieren optical system 33, a secondary optical system 34-1, a secondary optical system 34-2, a scanning unit 35, and a shim 36 are arranged.

  The one-dimensional modulation unit 32 includes, for example, a light source, a one-dimensional light modulation element as an example of a one-dimensional display element, an illumination optical system that causes light emitted from the light source to enter (irradiate) the one-dimensional light modulation element, and the like. Light for forming a two-dimensional image is emitted and is incident on the Schlieren optical system 33 from the entrance 51 of the exterior of the Schlieren optical system 33.

  Although the details of the one-dimensional modulation unit 32 will be described later, the light sources are arranged in the z-axis direction, emit light, and one-dimensional such as GLV arranged in the z-axis direction via the illumination optical system. The light is incident on the light modulation element. The one-dimensional light modulation element diffracts the light incident from the light source, spatially modulates the diffracted light generated thereby, and causes the spatially modulated light (diffracted light) to enter the Schlieren optical system 33 from the incident port 51. .

  The schlieren optical system 33 is composed of, for example, a plurality of mirrors, etc., and separates (blocks) a specific diffracted light component of the light incident from the one-dimensional modulation section 32 and schlieren the undiffracted diffracted light. The light is emitted from the outer emission port 52 of the optical system 33 and is incident on the secondary optical system 34-1 from the outer incident port 53 of the secondary optical system 34-1.

  The secondary optical system 34-1 and the secondary optical system 34-2 are optical systems for forming a two-dimensional image including a plurality of lenses. The secondary optical system 34-1 and the secondary optical system 34- 2 is symmetric with respect to the scanning unit 35 disposed between the two.

  The secondary optical system 34-1 collimates the light incident from the schlieren optical system 33 and emits the collimated light from the exit 54 of the exterior of the secondary optical system 34-1 in a direction parallel to the x axis. Then, the light is incident (irradiated) on the scanning mirror 55 of the scanning unit 35.

  The scanning unit 35 includes, for example, a galvanometer mirror and the like, and includes a scanning mirror 55 that reflects light from the secondary optical system 34-1 and a driving unit 56 that rotates the scanning mirror 55 in the direction of the arrow A1. Yes. The scanning mirror 55 is a flat mirror and is fixed to a rotation shaft (not shown) of the drive unit 56. The position of the center of rotation of the scanning mirror 55 is a position where the reflecting surface forms an angle of 45 degrees with respect to the light (x axis) incident from the secondary optical system 34-1. The light incident from the optical system 34-1 is reflected, and the reflected light is incident on the secondary optical system 34-2 from the entrance 57 of the exterior of the secondary optical system 34-2.

  The drive unit 56 rotates the rotation shaft of a galvano motor (not shown) of the drive unit 56 based on a drive signal supplied from a drive circuit (not shown), thereby moving the scanning mirror 55 fixed to the rotation shaft. With the straight line parallel to the z-axis (rotational axis of the galvano motor) as the axis, it is rotated in the direction of arrow A1, and the light applied to the scanning mirror 55 is scanned in the direction parallel to the x-axis. The drive unit 56 holds the galvano motor so as to fix the axial direction of the galvano motor. The light (light beam) scanned by the scanning unit 35 enters the secondary optical system 34-2 from the entrance 57 of the exterior of the secondary optical system 34-2.

  The secondary optical system 34-2 condenses the light (light flux) incident from the scanning unit 35, and emits the collected light from the exit port 58 of the exterior of the secondary optical system 34-2. A two-dimensional image is formed (formed) on a plane perpendicular to the optical axis of the optical system 34-2. Although not shown, for example, in the subsequent stage of the secondary optical system 34-2, a two-dimensional image emitted from the secondary optical system 34-2 is used as an intermediate image, and this is enlarged and projected onto a screen (not shown). The projection optical system projects the light (light flux) incident from the secondary optical system 34-2 onto the screen and displays a two-dimensional image on the screen.

  Further, a shim 36 is inserted between the base 31 and the drive unit 56 of the scanning unit 35 as necessary. The shim 36 is formed of, for example, a thin plate of metal or the like, and an inclined surface is provided on the surface of the shim 36 where the shim 36 and the driving unit 56 of the scanning unit 35 abut. Therefore, when the shim 36 is inserted between the base 31 and the driving unit 56 of the scanning unit 35, the scanning unit 35 (the scanning mirror 55 thereof) fixes (holds) the scanning mirror 55. The light incident on the reflecting surface of the scanning mirror 55 from the secondary optical system 34-1 is rotated about a straight line including the rotation axis of 56 galvanomotors and parallel to the straight line B1. The angle is adjusted.

  Each of the one-dimensional modulation unit 32, the schlieren optical system 33, and the secondary optical system 34-1 on the base 31 does not scan the light by rotating the scanning mirror 55 (the scanning mirror 55 is rotated in the direction of arrow A1). (When not moving) so that the light emitted from the one-dimensional modulation unit 32 forms an angle of 45 degrees with respect to the reflecting surface of the scanning mirror 55 via the schlieren optical system 33 and the secondary optical system 34-1 ( Although arranged so as to be incident on the scanning mirror 55 in parallel with the x-axis), a one-dimensional light modulation element such as GLV constituting the one-dimensional modulation unit 32, or the one-dimensional modulation unit 32 to secondary optics. If each optical element constituting each of the systems 34-1 is arranged to be inclined, the light incident on the scanning mirror 55 is inclined with respect to the z axis. In such a case, the image displayed by scanning the light for displaying the image with the scanning mirror 55 and projecting it onto the screen via the secondary optical system 34-2 is, for example, as shown in FIG. In addition, the image is not a rectangular image but a distorted image of a parallelogram.

  Therefore, as shown in FIG. 5, the shim 36 is inserted between the base 31 and the drive unit 56 of the scanning unit 35, and the scanning mirror 55 is tilted in the direction of the arrow A <b> 11 or the arrow A <b> 12, so By adjusting the angle at which the light from −1 is incident on the reflecting surface of the scanning mirror 55, image distortion can be corrected and a rectangular two-dimensional image without distortion can be displayed. Note that arrows R and Q indicate directions in which the x-axis and the y-axis are rotated by 45 degrees clockwise in the figure with the z-axis as the rotation axis, respectively. Further, in FIG. 5, the same reference numerals are given to the portions corresponding to those in FIG.

  For example, by inserting the shim 36 whose thickness in the z-axis direction becomes thinner from a predetermined position on the surface of the shim 36 in the direction of the arrow R between the base 31 and the drive unit 56, the scanning unit 35 is rotated in the direction of arrow A11 about a straight line passing through a point on the straight line including the rotation axis of the galvano motor of the drive unit 56 that fixes (holds) the scanning mirror 55 and is parallel to the arrow Q. Can be made.

  Similarly, scanning is performed by inserting the shim 36 whose thickness in the z-axis direction increases from a predetermined position on the surface of the shim 36 in the direction of the arrow R between the base 31 and the drive unit 56. The section 35 is rotated in the direction of the arrow A12 about a straight line that passes through a point on the straight line including the rotation axis of the galvano motor of the driving section 56 that fixes (holds) the scanning mirror 55 and is parallel to the arrow Q. Can be moved.

  Also, for example, the scanning unit 35 can be rotated in the direction of the arrow A11 by inserting a plurality of shims 36 having a constant thickness between the base 31 and the driving unit 56. In this case, the shim 36 is inserted into a part of the surface of the drive unit 56 where the drive unit 56 and the base 31 abut. Conversely, if the shims 36 inserted between the base 31 and the drive unit 56 are removed one by one, the scanning unit 35 can be rotated in the direction of the arrow A12.

  The angle at which the light from the secondary optical system 34-1 is incident on the reflection surface of the scanning mirror 55, that is, the angle at which the scanning unit 35 is tilted with respect to the base 31 is adjusted by rotating the scanning unit 35 itself. Instead, only the scanning mirror 55 may be rotated in the direction of arrow A11 or arrow A12, and a mechanism capable of linearly rotating the scanning unit 35 in the direction of arrow A11 or arrow A12 is scanned. You may make it provide in the part 35. FIG. Furthermore, by inserting a plurality of shims 36 one by one between the base 31 and the drive unit 56, the angle at which the scanning unit 35 is tilted with respect to the base 31 can be adjusted stepwise.

  In this way, by adjusting the angle at which the light from the secondary optical system 34-1 is incident on the reflection surface of the scanning mirror 55 (that is, the direction in which the light incident on the reflection surface of the scanning mirror 55 is reflected), For example, as shown in FIG. 6, even when linear light inclined with respect to the z-axis direction is incident on the reflecting surface of the scanning mirror 55 from the secondary optical system 34-1, the scanning mirror 55 (scanning unit) 35) to linear light parallel to the z-axis direction can be incident on the secondary optical system 34-2. In FIG. 6, parts corresponding to those in FIG. 5 are denoted by the same reference numerals, and the description thereof is omitted as appropriate because it is repeated. In more detail, the light incident on the reflecting surface of the scanning mirror 55 from the secondary optical system 34-1 has a spread in a direction parallel to the y-axis direction. In FIG. It is assumed that linear light having no spread in a direction parallel to the direction is incident.

  In the figure, point E1, point F1, point G1, and point H1 respectively indicate the vertices of the reflection surface of the rectangular scanning mirror 55, and point E1 ′ and point F1 ′ are point H1 and point H1, respectively. A point obtained by rotating the point E1 and the point F1 around the straight line passing through the G1 by a predetermined angle θ in the drawing is shown. A straight line connecting the points K1 and K2 represents linear light incident on the scanning mirror 55 from the secondary optical system 34-1 and the points K1 and K2 are respectively the secondary optical system 34-1. Represents the point (position) through which the end point of the linear light from.

  Further, each of the point J1, the point J3, the point K3, and the point K5 passes until the light emitted from the secondary optical system 34-1 and passing through the point K1 enters the secondary optical system 34-2. The points (positions) to be transmitted are shown. The light emitted from the secondary optical system 34-1 and passed through the point K2 to each of the points J2, K4, and K6 enters the secondary optical system 34-2. The points (positions) that pass before the incidence is shown.

  When the shim 36 is not inserted between the base 31 and the drive unit 56, that is, the angle at which the light from the secondary optical system 34-1 enters the reflecting surface of the scanning mirror 55 (on the reflecting surface of the scanning mirror 55). When the direction in which the incident light is reflected is not adjusted, the scanning mirror 55 has a straight line connecting the vertex E1 and the vertex H1 of the reflecting surface of the scanning mirror 55 and a straight line connecting the vertex F1 and the vertex G1, respectively. It arrange | positions on the base | substrate 31 so that it may become parallel to az axis. In this state, the light incident on the scanning mirror 55 from the secondary optical system 34-1 and the light incident on the secondary optical system 34-2 from the scanning mirror 55 are long lines in the direction parallel to the z axis, respectively. Ideally, it should be like light.

  Here, a case is considered where linear light represented by a straight line connecting the points K1 and K2 is emitted from the secondary optical system 34-1 in a direction opposite to the x-axis direction and is incident on the scanning mirror 55. . The straight line connecting the points K1 and K2 is a straight line obtained by inclining a straight line parallel to the z-axis direction by a predetermined angle in a direction opposite to the y-axis direction. At this time, of the linear light emitted from the secondary optical system 34-1, the light traveling through the point K1 and entering the reflecting surface of the scanning mirror 55 in the direction opposite to the x-axis direction is a point. Reflected at the point J1 on the reflecting surface of the rectangular scanning mirror 55 having the vertices at E1, point F1, point G1, and point H1, passes through the point K3, and enters the secondary optical system 34-2. . On the other hand, out of the linear light emitted from the secondary optical system 34-1, the light that passes through the point K2 and enters the reflecting surface of the scanning mirror 55 and proceeds in the direction opposite to the x-axis direction is the point E1. , Reflected at the point J2 on the reflection surface of the rectangular scanning mirror 55 having the points F1, G1, and H1 as vertices, passes through the point K4, and enters the secondary optical system 34-2.

  Therefore, linear light represented by a straight line connecting the point K3 and the point K4 enters the secondary optical system 34-2 from the scanning mirror 55. Here, the straight line connecting the points K3 and K4 is a straight line parallel to the straight line connecting the points K1 and K2, and the scanning mirror 55 is rotated about the straight line parallel to the z-axis direction. The linear light represented by the straight line connecting the points K3 and K4 is scanned in the x-axis direction or the direction opposite to the x-axis direction. As a result, the image that is displayed (projected) when light is emitted from the secondary optical system 34-2 and irradiated onto the screen via the projection optical system is not a rectangle but a parallelogram distorted. It becomes an image.

  On the other hand, a shim 36 is inserted between the base 31 and the drive unit 56, and the reflection surface of the scanning mirror 55 is set at a predetermined angle toward the front side in the figure with the straight line passing through the points H1 and G1 as an axis. When rotated by θ, that is, the angle at which the light from the secondary optical system 34-1 enters the reflecting surface of the scanning mirror 55 (the direction in which the light incident on the reflecting surface of the scanning mirror 55 reflects) is adjusted. In this case, the reflection surface of the scanning mirror 55 is represented by a rectangle having points E1 ′, F1 ′, G1 and H1 as vertices, and the vertexes E1 ′ and H1 of the reflection surface of the scanning mirror 55 are The connecting straight line and the straight line connecting the vertex F1 ′ and the vertex G1 are not parallel to the z axis, respectively.

  Here, consider a case where linear light represented by a straight line connecting the points K1 and K2 is emitted from the secondary optical system 34-1 and is incident on the scanning mirror 55. At this time, of the linear light emitted from the secondary optical system 34-1, the light traveling through the point K1 and entering the reflecting surface of the scanning mirror 55 in the direction opposite to the x-axis direction is a point. Reflected at the point J3 on the reflection surface of the rectangular scanning mirror 55 having the vertices at E1 ′, point F1 ′, point G1 and point H1, passes through the point K5, and enters the secondary optical system 34-2. Incident. On the other hand, out of the linear light emitted from the secondary optical system 34-1, the light that passes through the point K2 and enters the reflecting surface of the scanning mirror 55 and proceeds in the direction opposite to the x-axis direction is the point E1. Reflected at a point J2 on the reflecting surface of the rectangular scanning mirror 55 having apexes of ', point F1', point G1 and point H1, and passes through point K6 and enters the secondary optical system 34-2. To do.

  Therefore, linear light represented by a straight line connecting the point K5 and the point K6 enters the secondary optical system 34-2 from the scanning mirror 55. Here, the straight line connecting the point K5 and the point K6 is a straight line parallel to the z-axis, and the scanning mirror 55 uses the straight line passing through the point H1 and the point G1 as an axis and the straight line parallel to the z-axis by an angle θ. Since the light is rotated about a straight line parallel to the straight line rotated to the front side, the linear light represented by the straight line connecting the points K5 and K6 is in the x-axis direction or x Scanning is performed in a direction opposite to the axial direction. As a result, an image that is displayed (projected) when light exits the secondary optical system 34-2 and is further irradiated onto the screen via the projection optical system becomes a rectangular image without distortion. By inserting a shim 36 between the driving unit 56 and the scanning mirror 55 (scanning unit 35) by a predetermined angle, an image without distortion can be projected on the screen. Become.

  FIG. 7 is a diagram illustrating a more specific configuration example of the display device. In the figure, the dotted line represents the optical path of the light emitted from the one-dimensional modulation unit 32. Also, in FIG. 7, the same reference numerals are given to the portions corresponding to those in FIG.

  The one-dimensional modulation unit 32 is configured to include a light source 81, an illumination optical system 82, and a one-dimensional light modulation element 83. The light source 81 includes, for example, laser light sources such as a plurality of semiconductor lasers or solid-state lasers that emit red (R), green (G), and blue (B), respectively, and each of red, green, and blue light. Is made incident on the illumination optical system 82.

  For example, each of the laser light sources that emit red light that constitutes the light source 81 is arranged in a line in the z-axis direction (the direction parallel to the normal line of the xy plane and toward the front side in the figure) ( The red light emitted from the laser light sources is incident on the one-dimensional light modulation element 83 via the illumination optical system 82. Similarly, apart from the laser light source that emits red light, each of the laser light sources that emit green light that constitutes the light source 81 is arranged in a line in the z-axis direction, and the green light emitted by each laser light source is emitted. Is incident on the one-dimensional light modulation element 83 via the illumination optical system 82. Further, each of the laser light sources that emit blue light constituting the light source 81 is also arranged in a line in the z-axis direction, and the blue light emitted from each laser light source is 1 through the illumination optical system 82. The light enters the dimensional light modulation element 83.

  The illumination optical system 82 is composed of, for example, a plurality of lenses, collects the light incident from the light source 81, and causes the collected light to enter the one-dimensional light modulation element 83. For example, the illumination optical system 82 condenses red light, green light, and blue light incident from the light source 81 and collects light (linear light) of each color (red, green, blue). The light is incident on a one-dimensional light modulation element 83 for modulation.

  The one-dimensional light modulation element 83 modulates the red linear light, the green linear light, and the blue linear light incident from the illumination optical system 82, and converts the modulated light of each color. The light is incident on the schlieren optical system 33 via a dichroic mirror or a prism (not shown). More specifically, red light, green light, and blue light incident on the dichroic mirror or prism or the like from the one-dimensional light modulation element 83 are combined in the dichroic mirror or prism, and the combined light is The light enters the schlieren optical system 33 from the one-dimensional modulator 32.

  The one-dimensional light modulation element 83 is composed of, for example, GLVs for modulating the respective linear lights of red, green, and blue, and each of the GLVs for modulating the linear lights of the respective colors is a surface. A movable ribbon electrode (hereinafter referred to as a movable ribbon electrode) having a reflective film formed thereon, a fixed ribbon electrode (hereinafter referred to as a fixed ribbon electrode) having a reflective film formed on the surface thereof, and a polycrystal on a silicon substrate. A common electrode made of a silicon thin film is included.

  The movable ribbon electrode and the fixed ribbon electrode are alternately arranged on the common electrode along the z-axis direction, and each of the reflecting surfaces of the movable ribbon electrode and the fixed ribbon electrode (when the drive voltage is not applied) ( The surface on which the reflective film is formed is made equal in height from the common electrode.

  Further, when a driving voltage is applied to the movable ribbon electrode, an electrostatic force is generated between the movable ribbon electrode and the common electrode, and the movable ribbon electrode moves or deforms according to the electrostatic force, and the reflecting surface of the movable ribbon electrode The height from the common electrode to the reflecting surface of the fixed ribbon electrode is different (no longer coincident). Therefore, among the light incident from the illumination optical system 82, there is an optical path difference between the light reflected on the reflecting surface of the fixed ribbon electrode and the light reflected on the reflecting surface of the movable ribbon electrode. And diffracted light including a predetermined order is generated. The diffracted light generated in the GLV in this way is spatially modulated and is incident on a dichroic mirror or prism (not shown) in the subsequent stage.

  Here, an example in which GLV is used as the one-dimensional light modulation element has been described, but not limited to GLV, a DMD, a reflective liquid crystal element, or the like may be used.

  The light emitted from the one-dimensional modulation unit 32 enters the schlieren optical system 33. The schlieren optical system 33 includes a regular mirror 84, a secondary mirror 85, and a mirror 86.

  The regular mirror 84 is a mirror whose reflecting surface is concave in the direction opposite to the y-axis direction. The regular mirror 84 reflects the light incident from the one-dimensional modulation unit 32 and makes it incident on the secondary mirror 85. The secondary mirror 85 is a mirror whose reflection surface is convex in the y-axis direction, reflects the light incident from the regular mirror 84, and makes it incident on the regular mirror 84 again. The regular mirror 84 reflects the light incident from the secondary mirror 85 and causes the light to enter the mirror 86. The mirror 86 is a mirror having a planar reflection surface, and reflects the light incident from the regular mirror 84 so as to enter the secondary optical system 34-1. The light reflected by the mirror 86 forms (images) a one-dimensional image at a position immediately before entering the secondary optical system 34-1.

  The secondary optical system 34-1 is, for example, an equal-magnification imaging optical system having telecentricity, and is configured to include each of lenses 87 to 93 having rotationally symmetric surfaces around the optical axis. The secondary optical system 34-1 collimates the light incident from the schlieren optical system 33 by transmitting each of the lenses 87 to 93, and enters the collimated light (parallel light beam) to the scanning mirror 55. Let

  The refractive power of each of the lenses 87 to 93 is such that each of the lens 87, the lens 90, the lens 91, and the lens 92 has a positive power, and each of the lens 88, the lens 89, and the lens 93 is negative. Has power.

  The lens 88 is a negative meniscus lens, and the lens interval between the lens 88 and the lens 89 is relatively longer than the lens interval between other lenses, and the surface where the lens 88 and the lens 89 face each other is Both are concave. Furthermore, the surface (outgoing surface) facing the scanning mirror 55 of the lens 93 is also a concave surface.

  The light emitted from the secondary optical system 34-1 is reflected by the scanning mirror 55 and enters the secondary optical system 34-2. At this time, the scanning mirror 55 rotates about a straight line parallel to the z-axis, and scans the light incident from the secondary optical system 34-1 in the x-axis direction or the direction opposite to the x-axis direction. In addition, as described above, the scanning mirror 55 is rotated about a straight line parallel to a direction rotated by 45 degrees clockwise in the drawing as necessary, as described above. The angle at which the light from 34-1 enters the scanning mirror 55 (the reflection surface thereof) is adjusted.

  As described above, when the scanning mirror 55 is rotated to adjust the angle at which the light from the secondary optical system 34-1 enters the scanning mirror 55 (reflection surface thereof), the scanning mirror 55 is tilted. Although the optical path length from the secondary optical system 34-1 to the secondary optical system 34-2 changes, the secondary optical system 34-1 collimates the light incident from the schlieren optical system 33 and generates parallel rays. Since the generated parallel rays are incident on the secondary optical system 34-2 via the scanning mirror 55, the influence on the focus shift is small.

  The secondary optical system 34-2 is, for example, an equal-magnification imaging optical system having telecentricity, and is configured to include each of the lenses 94 to 100 having rotationally symmetric surfaces around the optical axis. The secondary optical system 34-2 collects the light (parallel light beam) incident from the scanning mirror 55 by transmitting through each of the lenses 94 to 100, and collects it on the optical axis of the secondary optical system 34-2. A two-dimensional image is formed on a vertical image plane 121 (a plane parallel to the xz plane).

  Each of the lenses 94 to 100 is symmetrically arranged with each of the lens 93, the lens 92, the lens 91, the lens 90, the lens 89, the lens 88, and the lens 87 with the scanning mirror 55 interposed therebetween. The lenses 100 to 100 have the same lens parameters as the corresponding lenses 87 to 93, respectively. The refractive power of each of the lenses 94 to 100 is such that each of the lens 94, the lens 98, and the lens 99 has negative power, and each of the lens 95, the lens 96, the lens 97, and the lens 100 has a negative power. Has positive power.

  Further, the lens 99 is a negative meniscus lens, and the lens interval between the lens 99 and the lens 98 is relatively longer than the lens interval between the other lenses, and the surface where the lens 99 and the lens 98 face each other is Both are concave. Further, the surface (outgoing surface) of the lens 94 facing the scanning mirror 55 is also concave.

  Here, the specifications of the schlieren optical system 33 and the specifications of the secondary optical system 34-1, the scanning mirror 55, and the secondary optical system 34-2 are shown in Table 1 and Table 2, respectively. Regarding the F number of the optical system including the secondary optical system 34-1, the scanning mirror 55, and the secondary optical system 34-2, the arrangement direction of the ribbon electrodes constituting the one-dimensional light modulation element 83 (hereinafter referred to as long) The z-axis direction is 10, and the light scanning direction is 5. The range of the incident angle of light incident on the reflecting surface of the scanning mirror 55 from the secondary optical system 34-1 is 45 ± 9.5 degrees. When the length of the one-dimensional light modulation element 83 in the major axis direction (z-axis direction) is “14” in arbitrary units, the size of the two-dimensional image is a rectangle of “32.9 × 14” (arbitrary units). (The length 32.9 of the long side indicates the length in the direction in which the light is scanned, and is the same magnification in the z-axis direction).

  Tables 1 and 2 include the surface number representing the entrance surface or exit surface of each lens or the reflecting surface of the mirror, the radius of curvature of the surface represented by the surface number, and the surface represented by the surface number to the next surface. The surface distance to the surface represented by the number, the effect of the surface, the lens material, and the rotation angle (remarks) are shown.

  In Table 1, “OBJ” represents an object point (one-dimensional light modulation element 83). Surface number 1 and surface number 3 represent the reflecting surface of the regular mirror 84, surface number 2 represents the reflecting surface of the secondary mirror 85, and surface number 4 represents the reflecting surface of the mirror 86.

  In Table 2, the surface number 5, surface number 7, surface number 9, surface number 11, surface number 13, surface number 15, and surface number 17 are the light incident surfaces of the lenses 87 to 93, respectively. (Surfaces on which light from the schlieren optical system 33 is incident on the respective lenses), surface number 6, surface number 8, surface number 10, surface number 12, surface number 14, surface number 16, and surface Reference numeral 18 represents each of the light emission surfaces (surfaces from which the light from the schlieren optical system 33 is emitted from the respective lenses) of the lenses 87 to 93.

  Further, the surface number 19 represents the reflection surface of the scanning mirror 55, and each of the surface number 20, the surface number 22, the surface number 24, the surface number 26, the surface number 28, the surface number 30, and the surface number 32 is Each of the light incident surfaces (surfaces on which light from the scanning mirror 55 is incident on each lens) of the lenses 94 to 100 is represented by surface number 21, surface number 23, surface number 25, and surface number 27. , Surface number 29, surface number 31, and surface number 33 represent the light emission surfaces (surfaces from which the light from the scanning mirror 55 is emitted from the respective lenses) of the lenses 94 to 100, respectively. Yes. Furthermore, “IMG” represents the image plane 121 (two-dimensional image plane).

  Further, the surface spacings in Tables 1 and 2 are reversed in sign by reflection at the primary mirror 84, the secondary mirror 85, and the mirror 86, respectively, and further, by reflection at the scanning mirror 55, the lenses 94 to In the lens 100, the sign is reversed.

  Furthermore, in the operation of the surfaces in Tables 1 and 2, “REFL” represents a reflective surface, and those not displayed (except OBJ and IMG) represent a transmissive surface. Each of “ADE”, “BDE”, and “CDE” in the remark is an axis in a direction parallel to the z axis in FIG. 7 and an axis perpendicular to the Y axis and perpendicular to each other is an X axis and a Z axis. Further, when the optical axis direction is the Z-axis direction, the rotation angles (units: degrees) about the X-axis, the Y-axis, and the Z-axis as the central axes are shown. In the example of Table 2, the reflection surface of the scanning mirror 55 whose surface number is 19 is set at an angle of 45 degrees with respect to the incident-side optical axis, and is reflected by the reflection surface at an angle of 90 degrees (reflection angle 45 degrees). The light is scanned at a predetermined angle (± 9.5 degrees) with the light to be scanned as the center. Note that the coordinate systems in the tables shown in Tables 1 and 2 are set locally (for example, the setting direction of the coordinate system is changed by reflection).

  Further, as can be seen from Table 2, on the basis of the reflection surface of the scanning mirror 55 represented by the surface number 19, the surfaces having the sum of the surface numbers of 38 have the same parameter value (for example, the lens 88). Further, a lens configuration having symmetry with respect to the reflection surface of the scanning mirror 55 is employed. Each lens surface (incident surface and outgoing surface) is a spherical surface.

  Further, the distance (39.56) between the lens 88 and the lens 89, or the lens 98 and the lens 99 is set to be within 30 to 50% of the focal length “100” (arbitrary unit) of the entire lens system including the lenses 87 to 100. Both opposing surfaces of the lenses are concave. The lenses 88 and 99 are meniscus lenses.

  Furthermore, some of the lenses (for example, the lens 87, the lens 90, the lens 97, and the lens 100) constituting the secondary optical system 34-1 or the secondary optical system 34-2 have an Abbe number of 80 or more. It is formed using low dispersion glass (FCD1_HOYA: refractive index Nd = 1.490000, Abbe number νd = 81.6). In addition, the lens 91, the lens 92, the lens 94, and the lens 95 are formed using high refractive index glass (TAFD5_HOYA: refractive index Nd = 1.83500, TAF1_HOYA: refractive index Nd = 1.77250) having a refractive index of 1.7 or more. ing.

  Next, the lateral aberration of the optical system including the secondary optical system 34-1, the scanning mirror 55, and the secondary optical system 34-2 will be described with reference to FIGS.

  Each of FIGS. 8 to 12 is a diagram showing lateral aberration when the wavelength of light for forming a two-dimensional image is a wavelength λ = 532 nm. In FIG. 45 degrees with respect to the light incident from the secondary optical system 34-1 (straight line parallel to the incident direction), and in FIG. 9, the reflecting surface of the scanning mirror 55 reflects the light incident from the secondary optical system 34-1. In FIG. 10, the reflection surface of the scanning mirror 55 forms (45 + 5) degrees with respect to the light incident from the secondary optical system 34-1, and in FIG. 55 has a (45 + 7.5) degree with respect to the light incident from the secondary optical system 34-1, and in FIG. 12, the reflective surface of the scanning mirror 55 is incident from the secondary optical system 34-1. Each case shows (45 + 9.5) degrees with respect to the light.

  8 to 12, the object heights 0, 7, 10, and 14 are shown in order from the bottom. In the drawing, the left side shows aberrations in the major axis direction of the one-dimensional light modulator 83, and the right side shows the right side. Aberration in the direction of scanning light is shown. 8 to 12, “Y-FAN” means that the axis parallel to the z-axis in FIG. 7 is the Y-axis, the axes perpendicular to the Y-axis and perpendicular to each other are the X-axis and the Z-axis, When the optical axis direction is the Z-axis direction, the Y-axis direction is the arrangement direction of the one-dimensional light modulation elements 83, and the Z-axis direction is the optical axis direction. Is displayed. Similarly, “X-FAN” represents an XZ plane when light is scanned in the X-axis direction. In the examples of FIGS. 8 to 12, the size of one pixel is 0.25, indicating high imaging performance.

  By the way, as shown in FIG. 5, the scanning mirror 55 is rotated in the direction of the arrow A11 or the arrow A12, and the angle at which the light from the secondary optical system 34-1 enters the reflecting surface of the scanning mirror 55 is set. When adjusted, the optical path length from the exit surface of the lens 93 to the reflection surface of the scanning mirror 55 of the light incident on the reflection surface of the scanning mirror 55 from the lens 93 (FIG. 7) and the reflection surface of the scanning mirror 55 to the lens 94 ( The optical path length of the light incident on FIG. 7) from the reflecting surface of the scanning mirror 55 to the incident surface of the lens 94 changes.

  The secondary optical system 34-2 shown in FIG. 7 has a configuration in which a so-called plane tilt or focus shift hardly occurs on the image plane 121 even when the optical path length is changed by rotating the scanning mirror 55 in this way. It is said that.

  Here, in the figure of the two-dimensional image 161 formed on the image plane 121 (FIG. 7) shown in FIG. 13, the two-dimensional image 161 included in the right portion (portion surrounded by a dotted line). Consider the focus shift in the X1 direction and the focus shift in the Y1 direction at the upper points P1 to P9. In the figure, the X1 direction is a direction opposite to the x-axis direction in FIG. 7, and the Y1 direction is a direction parallel to the z-axis direction in FIG.

  In FIG. 13, straight lines passing through each of the points P2, P5, and P8 are parallel to the X1 direction, and similarly, straight lines passing through the points P1, P4, and P7 are The straight line is parallel to the X1 direction, and the straight line passing through each of the points P3, P6, and P9 is a straight line parallel to the X1 direction. Further, the straight lines passing through each of the points P1 to P3 are parallel to the Y1 direction, and similarly, the straight lines passing through each of the points P4 to P6 are parallel to the Y1 direction. The straight lines passing through the points P7 to P9 are parallel to the Y1 direction.

  The distance from the point P1 to the point P2 and the distance from the point P1 to the point P3 are 14 (arbitrary unit (for example, 14 mm)). Further, the scanning mirror 55 is disposed so that the optical axis of the optical system including the secondary optical system 34-1, the scanning mirror 55, and the secondary optical system 34-2 passes through the center of the reflection surface of the scanning mirror 55. ing. Here, the center of the reflection surface of the scanning mirror 55 is, for example, when the reflection surface of the scanning mirror 55 is a rectangle having the vertexes E1, F1, G1, and H1 shown in FIG. An intersection of a straight line connecting the vertex E1 and the vertex G1 and a straight line connecting the vertex F1 and the vertex H1.

  When the reflecting surface of the scanning mirror 55 is at a position that forms an angle of 45 degrees with respect to the light incident from the secondary optical system 34-1 (hereinafter also referred to as a reference position), that is, the secondary optical system 34-1. Is incident on the reflecting surface of the scanning mirror 55 at an angle of 45 degrees, the light reflected on the reflecting surface of the scanning mirror 55 is transmitted through the secondary optical system 34-2, and the point P2 and An image (one-dimensional image) is connected on a straight line connecting the points P3.

  Then, when the scanning mirror 55 is rotated by 3.5 degrees so that the reflection surface of the scanning mirror 55 faces the right direction in the drawing with a straight line parallel to the Y1 direction of FIG. 13 as an axis, In FIG. 7, when the scanning mirror 55 is rotated by 3.5 degrees clockwise from the reference position about a straight line parallel to the z-axis direction (the rotation axis of the scanning unit 35), the scanning mirror The light reflected by the reflecting surface 55 passes through the secondary optical system 34-2 and forms an image (one-dimensional image) on a straight line connecting the points P5 and P6.

  Further, when the scanning mirror 55 is further rotated by 3.5 degrees so that the reflection surface of the scanning mirror 55 faces the right direction in the drawing with a straight line parallel to the Y1 direction of FIG. 13 as an axis, That is, in FIG. 7, when the scanning mirror 55 is rotated by 7 degrees clockwise in the drawing around the straight line (rotation axis of the scanning unit 35) parallel to the z-axis direction from the reference position, The light reflected by the reflection surface 55 passes through the secondary optical system 34-2 and forms an image (one-dimensional image) on a straight line connecting the points P8 and P9.

  Here, for example, the scanning mirror 55 is rotated by 0.1 degree in the direction of the arrow A11 (FIG. 5) about the straight line passing through the center of the reflection surface of the scanning mirror 55 and parallel to the direction of the arrow Q in FIG. When moved, the left and right side edges (for example, the side represented by the straight line connecting the points P8 and P9) in the figure of the two-dimensional image 161 (FIG. 13) can be tilted to the left by 0.07 degrees. That is, the image distortion can be corrected by 0.07 degrees.

  In this case, for example, as shown in FIG. 14A, the light incident on the scanning mirror 55 from the secondary optical system 34-1 is represented by an arrow A31, and the light incident on the scanning mirror 55 is reflected on the reflection surface of the scanning mirror 55. If the light of the coordinate system orthogonal to each other is represented by the X2 axis, the Y2 axis, and the Z2 axis, the scanning mirror 55 is shown on the upper side of the scanning mirror 55 in FIG. (Side represented by a straight line connecting the point E1 and the point F1) is rotated by 0.1 degree in the direction of rotating to the near side. In the figure, portions corresponding to those in FIG. 6 are denoted by the same reference numerals, and the description thereof is omitted because it is repeated.

  In FIG. 14A, the intersection of the straight line connecting the point E1 and the point G1 and the straight line connecting the point F1 and the point H1 is the center of the reflecting surface of the scanning mirror 55, and each of the X2, Y2, and Z2 axes. Pass through the center of the reflection surface of the scanning mirror 55. The X2 axis is parallel to the straight line connecting the point E1 and the point F1, and the straight line connecting the point H1 and the point G1, and the Y2 axis is the straight line connecting the point E1 and the point H1, and the point F1. And the Z2 axis are parallel to the normal line of the reflection surface of the scanning mirror 55 including the point E1, the point F1, the point G1, and the point H1.

  Further, when the scanning mirror 55 shown in FIG. 14A is viewed from the upper side to the lower side (the direction opposite to the Y2-axis direction) in the drawing, the light represented by the arrow A31 is two-dimensional optical as shown in FIG. 14B. The light enters the scanning mirror 55 from the system 34-1 and is reflected by the scanning mirror 55 and is incident on the secondary optical system 34-2 as represented by an arrow A32. Furthermore, the X2 axis is in contact with the reflecting surface of the scanning mirror 55, and the Z2 axis is perpendicular to the reflecting surface of the scanning mirror 55.

  As described above, when the scanning mirror 55 is rotated by 0.1 degree in the direction of the arrow A11 (FIG. 5), the focus shift in the X1 direction and the focus shift in the Y1 direction at the points P1 to P9 are as shown in FIG. As shown. Note that the focus shift in the X1 direction and the focus shift in the Y1 direction are points P1 to P1 when the scanning mirror 55 is not rotated (the scanning mirror 55 is not rotated in the direction of arrow A11 or arrow A12 in FIG. 5). This is a relative value with respect to the focus shift in the X1 direction and the focus shift in the Y1 direction at P9, and the unit is “μm” for both.

  FIG. 15 shows a position on the two-dimensional image 161, a focus shift in the X1 direction at that position, and a focus shift in the Y1 direction. For example, the focus shift in the X1 direction at the point P1 is 1.3, and the focus shift in the Y1 direction at the point P1 is 0. Further, the focus shift in the X1 direction at the point P2 is 0.2, the focus shift in the Y1 direction at the point P2 is 1.3, the focus shift in the X1 direction at the point P3 is -2.4, and the point P3 The focus shift in the Y1 direction at −3 is −1.3, the focus shift in the X1 direction at the point P4 is 0, and the focus shift in the Y1 direction at the point P4 is 0.

  Further, the focus shift in the X1 direction at the point P5 is 0.8, the focus shift in the Y1 direction at the point P5 is 0.8, the focus shift in the X1 direction at the point P6 is -0.8, and the point P6 The focus shift in the Y1 direction at − is 0.8, the focus shift in the X1 direction at the point P7 is 0, and the focus shift in the Y1 direction at the point P7 is 0. Further, the focus shift in the X1 direction at the point P8 is −0.8, the focus shift in the Y1 direction at the point P8 is −0.5, and the focus shift in the X1 direction at the point P9 is 0.8. The focus shift in the Y1 direction at the point P9 is 0.5.

  Among the points P1 to P9, the maximum value (absolute value) of the focus shift in the X1 direction is 2.4, and among the points P1 to P9, the maximum value of the focus shift in the Y1 direction (absolute) (Value) is 0.8, and it can be seen that the focus shift is sufficiently small. Further, when a difference in focus deviation between the upper end point P2 of the two-dimensional image 161 and the lower end point P3 of the two-dimensional image 161 is taken, the X1 direction focus deviation at the point P2 and the X1 direction focus deviation at the point P3. Is 2.6 (0.2 − (− 2.4)), and the difference between the focus shift in the Y1 direction at the point P2 and the focus shift in the Y1 direction at the point P3 is 2.6 ( 1.3-(-1.3), it can be seen that the focus shift is sufficiently small and the focus position (focus direction) is hardly tilted.

  On the other hand, for example, a straight line passing through the center of the reflecting surface of the mirror 86 (FIG. 7) and parallel to the direction in which the x-axis is rotated 45 degrees clockwise with the z-axis of FIG. When the mirror 86 is rotated by 0.05 degrees in the direction in which the reflecting surface of the mirror 86 faces in the direction opposite to the z-axis direction, the above-described scanning mirror 55 is rotated by 0.1 degrees. Similarly, in the figure of the two-dimensional image 161 (FIG. 13), the left and right sides (for example, the side represented by the straight line connecting the points P8 and P9) can be tilted to the left by 0.07 degrees. Image distortion can be corrected by 0.07 degrees.

  In this case, for example, as shown in FIG. 16A, the light incident on the mirror 86 from the regular mirror 84 is represented by an arrow A51, and the light incident on the mirror 86 is reflected on the reflecting surface of the mirror 86 by an arrow A52. If the axes of the coordinate system orthogonal to each other are the X3 axis, the Y3 axis, and the Z3 axis, the mirror 86 with the X3 axis as the axis (rotation axis) is shown as the upper side (point E21 and point F21 in the figure of the mirror 86). The side represented by a straight line connecting the two is rotated by 0.05 degrees in the direction of rotating to the near side. Note that point E21, point F21, point G21, and point H21 each represent the vertex of the reflection surface of the mirror 86 that is rectangular.

  In FIG. 16A, the intersection of the straight line connecting the point E21 and the point G21 and the straight line connecting the point F21 and the point H21 is the center of the reflecting surface of the mirror 86, and each of the X3 axis, the Y3 axis, and the Z3 axis is The mirror 86 passes through the center of the reflection surface. The X3 axis is parallel to a straight line connecting the point E21 and the point F21 and a straight line connecting the point H21 and the point G21, and the Y3 axis is a straight line connecting the point E21 and the point H21, and the point F21. And the Z3 axis are parallel to the normal line of the reflecting surface of the mirror 86 including the point E21, the point F21, the point G21, and the point H21.

  Further, when the mirror 86 shown in FIG. 16A is viewed from the upper direction to the lower direction (the direction opposite to the Y3 axis direction) in the drawing, the light represented by the arrow A51 is transmitted from the regular mirror 84 as shown in FIG. 16B. As shown by the arrow A52, the light enters the mirror 86, is reflected by the mirror 86, and enters the secondary optical system 34-1. Furthermore, the X3 axis is in contact with the reflecting surface of the mirror 86, and the Z3 axis is perpendicular to the reflecting surface of the mirror 86.

  As described above, when the mirror 86 is rotated by 0.05 degrees, the focus shift in the X1 direction and the focus shift in the Y1 direction at the points P1 to P9 are as shown in FIG. The defocus in the X1 direction and the defocus in the Y1 direction are relative values to the defocus in the X1 direction and the defocus in the Y1 direction at the points P1 to P9 when the mirror 86 is not rotated. The unit is “μm”.

  FIG. 17 shows a position on the two-dimensional image 161, a focus shift in the X1 direction at that position, and a focus shift in the Y1 direction. For example, the focus shift in the X1 direction at the point P1 is 0.1, and the focus shift in the Y1 direction at the point P1 is 0.1. Further, the focus shift in the X1 direction at the point P2 is −18.6, the focus shift in the Y1 direction at the point P2 is −18.7, and the focus shift in the X1 direction at the point P3 is 18.6. The focus shift in the Y1 direction at P3 is 18.9, the focus shift in the X1 direction at point P4 is 0.1, and the focus shift in the Y1 direction at point P4 is 0.1.

  Further, the focus shift in the X1 direction at the point P5 is −18.7, the focus shift in the Y1 direction at the point P5 is −18.2, and the focus shift in the X1 direction at the point P6 is 18.9. The focus shift in the Y1 direction at P6 is 18.4, the focus shift in the X1 direction at point P7 is 0.7, and the focus shift in the Y1 direction at point P7 is -0.5. Further, the focus shift in the X1 direction at the point P8 is -17.8, the focus shift in the Y1 direction at the point P8 is -17.4, and the focus shift in the X1 direction at the point P9 is 18.0. The focus shift in the Y1 direction at the point P9 is 17.6.

  Among the points P1 to P9, the maximum value (absolute value) of the focus shift in the X1 direction is 18.9, and among the points P1 to P9, the maximum value of the focus shift in the Y1 direction (absolute) Value) is 18.4, which is compared with the maximum defocus value 2.4 in the X1 direction and the maximum defocus value 0.8 in the Y1 direction in FIG. 15 (when the scanning mirror 55 is rotated). It can be seen that the focus shift is very large.

  Further, when a difference in focus deviation between the upper end point P2 of the two-dimensional image 161 and the lower end point P3 of the two-dimensional image 161 is taken, the X1 direction focus deviation at the point P2 and the X1 direction focus deviation at the point P3. The difference between the focus shift in the Y1 direction at the point P2 and the focus shift in the Y1 direction at the point P3 is -37.4 (-18.6- (18.8)). 6 (−18.7− (18.9)), and the difference between the focus shift in the X1 direction at the point P2 and the focus shift in the X1 direction at the point P3 in FIG. 15 (when the scanning mirror 55 is rotated). Compared with 2.6, the difference between the focus shift in the Y1 direction at point P2 and the focus shift in the Y1 direction at point P3, the difference in focus shift is large. 3 indicates that the focus position (focus direction) is greatly tilted, that is, when the mirror 86 is rotated to correct the distortion of the two-dimensional image 161, the two-dimensional image becomes light. It turns out that it falls down greatly in the axial direction.

  As described above, the light emitted from the element (mirror 86 in the case of FIG. 17) that performs adjustment for correcting the distortion of the two-dimensional image is subject to surface tilt or defocusing via another imaging optical system. Adjustment for correcting distortion of a two-dimensional image when incident on a secondary optical system 34-2 that is not likely to occur, that is, when light that is not a parallel beam enters the secondary optical system 34-2 In the imaging optical system (for example, the secondary optical system 34-1) between the element that performs the above and the secondary optical system 34-2, a focus shift occurs. In such a case, the positions of the secondary optical system 34-1 and the secondary optical system 34-2 are adjusted again to correct the focus shift, and the position of each element constituting the optical system is adjusted. Becomes complicated.

  Further, as a method of correcting the distortion of the two-dimensional image, the position of the light source 81, the lens of the illumination optical system 82, or the one-dimensional light modulation element 83 constituting the one-dimensional modulation unit 32 can be adjusted. Also when adjusting the position of the element which comprises the one-dimensional modulation part 32, adjustment of the position of each element will become complicated. For example, when correcting the distortion of a two-dimensional image by adjusting the position of the one-dimensional light modulation element 83, the one-dimensional light modulation element 83 that modulates red (R) light, the green (G) light is modulated. The positions of the one-dimensional light modulation element 83 and the one-dimensional light modulation element 83 that modulates blue (B) light must be adjusted.

  On the other hand, the scanning mirror 55 (scanning unit 35) is rotated so that the light is incident on the secondary optical system 34-2 that is not easily tilted or out of focus. In the case of correction, the light emitted from the scanning mirror 55 is a parallel light beam and directly enters the secondary optical system 34-2 without going through the imaging optical system, so that almost no surface tilt or focus deviation occurs. The distortion of the two-dimensional image can be corrected. In the drawing of the two-dimensional image 161 in FIG. 13, only the focus shift at the points included in the right part has been described, but the same applies to the left part of the two-dimensional image 161, and the points P2 and P3 are connected. A symmetrical result is obtained with respect to the straight line.

  Next, referring to the flowchart of FIG. 18, an operator who assembles the display device makes an angle at which the light from the secondary optical system 34-1 enters the scanning mirror 55 (the light incident on the reflecting surface of the scanning mirror 55 The process of adjusting the angle of the scanning mirror for adjusting the reflection direction will be described.

  In step S11, each element constituting each of the one-dimensional modulation unit 32, the schlieren optical system 33, the secondary optical system 34-1, the scanning unit 35, and the secondary optical system 34-2 is arranged on the base 31. .

  In step S12, the light source 81 emits light. When the light source 81 emits light, the light emitted from the light source 81 enters the one-dimensional light modulation element 83 via the illumination optical system 82. The light incident on the one-dimensional light modulation element 83 is modulated by the one-dimensional light modulation element 83 and enters the scanning mirror 55 via the schlieren optical system 33 and the secondary optical system 34-1.

  When light is incident on the scanning mirror 55 from the secondary optical system 34-1, in step S13, the scanning mirror 55 reflects the light incident from the secondary optical system 34-1 to the secondary optical system 34-2. Make it incident.

  In step S <b> 14, the secondary optical system 34-2 collects the light incident from the scanning mirror 55 and projects the collected light onto the screen via the projection optical system at the subsequent stage, so that a linear image (1 Dimensional image). That is, the secondary optical system 34-2 collects the light incident from the scanning mirror 55, and causes the collected light to enter the subsequent projection optical system. Then, the projection optical system enlarges the light incident from the secondary optical system 34-2 and projects the light on a screen to display a linear image.

  In step S15, the shim 36 is inserted between the base 31 and the drive unit 56 as necessary, so that the scanning unit 35 (scanning mirror 55) is rotated and the secondary optical system 34-1. The angle at which the light enters the scanning mirror 55 is adjusted. At this time, for example, the angle at which the light from the secondary optical system 34-1 enters the scanning mirror 55 is as shown in FIG. 5 by inserting the shim 36 between the base 31 and the drive unit 56. In addition, the scanning unit 35 (scanning mirror 55) is rotated in the direction of the arrow A11 or the arrow A12, and the linear image displayed on the screen is displayed on the screen, for example, at a desired angle. The linear image is adjusted so as to be parallel to the z-axis direction in FIG. Further, if necessary, the positions of the secondary optical system 34-2 and the elements (for example, lenses) constituting the projection optical system are adjusted, and the scanning mirror angle adjustment process ends.

  In this manner, the shim 36 is inserted between the base 31 and the drive unit 56 as necessary, whereby the scanning unit 35 (scanning mirror 55) is rotated, and the secondary optical system 34-1. The angle at which the light from the light enters the scanning mirror 55 is adjusted.

  In this way, by adjusting the angle at which the light from the secondary optical system 34-1 enters the scanning mirror 55, the display device can display an image with less distortion on the screen.

  Further, the display device is not limited to the configuration shown in FIG. 7, and may be configured as shown in FIG. 19, for example. In FIG. 19, parts corresponding to those in FIG. 7 are denoted by the same reference numerals, and the description thereof is omitted as appropriate because it is repeated.

  The display device shown in FIG. 19 has a configuration in which a mirror 201 is newly provided between the secondary optical system 34-1 and the scanning mirror 55 (scanning unit 35) of the display device shown in FIG. The reflection surface of the mirror 201 is arranged so as to be parallel to a direction rotated about 45 degrees counterclockwise about the y axis with the z axis as an axis. The scanning mirror 55 is also a reflection surface of the mirror 201. And the reflecting surface of the scanning mirror 55 are arranged in parallel.

  The mirror 201 reflects the light traveling from the secondary optical system 34-1 and proceeding in the y-axis direction in the x-axis direction and makes it incident on the scanning mirror 55. The scanning mirror 55 reflects the light incident from the mirror 201 in the y-axis direction and makes it incident on the secondary optical system 34-2. The scanning mirror 55 rotates about a straight line parallel to the z-axis, and scans the light from the mirror 201 in the x-axis direction or the direction opposite to the x-axis direction.

  Here, the adjustment for correcting the distortion of the image displayed on the screen is performed by rotating the mirror 201 instead of rotating the scanning mirror 55 (scanning unit 35). That is, for example, by inserting the shim 36 between the base 31 and the mirror 201, the z axis is the axis, and the y axis is rotated counterclockwise by 45 degrees. By rotating the mirror 201, the distortion of the image displayed on the screen is corrected by adjusting the angle at which the light from the secondary optical system 34-1 enters the reflecting surface of the mirror 201. Since the light (parallel light beam) emitted from the mirror 201 enters the secondary optical system 34-2 without passing through the imaging optical system, it is displayed on the screen without causing a focus shift as described above. Image distortion can be corrected.

  As described above, the adjustment for correcting the distortion of the image displayed on the screen is not limited to the scanning unit 35 and is arranged between the secondary optical system 34-1 and the secondary optical system 34-2. This can be done by rotating (tilting) a mirror or the like. Although it has been described that a galvanometer mirror is used as the scanning unit 35, for example, a configuration using a polygon mirror or the like is also possible.

  As described above, according to the present invention, since light is emitted for displaying an image, the image can be displayed. In addition, according to the present invention, since elements such as a mirror disposed between secondary optical systems for forming a two-dimensional image are rotated, a display device using a one-dimensional display element is used. Thus, an image with less distortion can be displayed.

It is a figure explaining the distortion of the image which arises when a two-dimensional display element is used. It is a figure explaining the direction which the display apparatus using a one-dimensional display element scans a one-dimensional image. It is a figure explaining the distortion of the image which arises when a one-dimensional display element is used. It is a perspective view which shows the structural example of the display apparatus to which this invention is applied. It is a figure explaining adjustment of the angle in which the light from a secondary optical system injects into the reflective surface of a scanning mirror. It is a figure explaining adjustment of the angle in which the light from a secondary optical system injects into the reflective surface of a scanning mirror. It is a figure which shows the more specific structural example of a display apparatus. It is a figure which shows the lateral aberration of an optical system. It is a figure which shows the lateral aberration of an optical system. It is a figure which shows the lateral aberration of an optical system. It is a figure which shows the lateral aberration of an optical system. It is a figure which shows the lateral aberration of an optical system. It is a figure explaining the focus shift | offset | difference of a two-dimensional image. It is a figure explaining the direction which rotates a scanning mirror. It is a figure explaining the focus shift | offset | difference of a two-dimensional image when a scanning mirror is rotated. It is a figure explaining the direction which rotates a mirror. It is a figure explaining the focus shift | offset | difference of a two-dimensional image when a mirror is rotated. It is a flowchart explaining the process of angle adjustment of a scanning mirror. It is a figure which shows the structural example of a display apparatus.

Explanation of symbols

  31 substrate, 32 one-dimensional modulation unit, 33 schlieren optical system, 34-1, 34-2 secondary optical system, 35 scanning unit, 36 shim, 55 scanning mirror, 56 driving unit, 81 light source, 83 one-dimensional light modulation element , 87 lens, 88 lens, 89 lens, 90 lens, 91 lens, 92 lens, 93 lens, 94 lens, 95 lens, 96 lens, 97 lens, 98 lens, 99 lens, 100 lens, 201 mirror

Claims (4)

The reflecting surface of the reflecting means for reflecting the light for forming the first image, which is a parallel light beam, is rotated about a predetermined first straight line, and the first image reflected on the reflecting surface is reflected. Adjusting means for adjusting the angle of the light for forming the second straight line perpendicular to the traveling direction of the light for forming the first image;
Light for forming the first image, which is a parallel light beam reflected by the reflecting means, perpendicular to the traveling direction of the light for forming the first image and on the second straight line The light for forming the first image scanned in the direction parallel to the third vertical straight line is collected, and the first scanned on the first plane perpendicular to the optical axis is collected. An optical apparatus comprising: an image forming unit that forms a second image composed of an image. The said adjustment means adjusts the angle with respect to the said 2nd straight line of the light for forming the said 1st image which injected into the reflective surface of the galvanometer mirror as said reflection means. Optical equipment. Collimating means for collimating incident light to generate light for forming the first image, which is a parallel light beam, and causing the generated light for forming the first image to enter the reflecting means The optical apparatus according to claim 1, further comprising: The light for forming the first image, which is a parallel light beam scanned in a direction parallel to the first straight line perpendicular to the traveling direction of the light for forming the first image, is collected, and the light Light for forming the first image, which is a parallel light beam, is applied to an imaging unit that forms a second image composed of the scanned first image on a first plane perpendicular to the axis. A reflecting step for reflecting the light on the reflecting surface of the reflecting means and making it incident;
The reflecting surface of the reflecting means is rotated about a predetermined second straight line as an axis, and a third perpendicular to the traveling direction of light for forming the first image is perpendicular to the first straight line. An adjustment step of adjusting an angle of light for forming the first image reflected on the reflecting surface with respect to a straight line.

Images