JP2013011675A - Observation optical apparatus - Google Patents

Abstract

An object of the present invention is to display images with a wide angle of view and a reduced number of parallax images to be presented to an observer while reducing visual fatigue by performing super multi-view display that presents a plurality of parallax images within an observer's monocular. An optical apparatus for observation capable of keeping down the frame rate required for the section is provided.
An observation optical apparatus (5) for causing a plurality of parallax images to be incident on one eye, an opening forming unit (6) capable of changing a region where an opening is formed, and the plurality of parallax images. Based on the signal from the signal synchronization means (4, 9, 7, 8) for synchronizing the image display means (1) for displaying in time series and the opening formation means, and the signal from the signal synchronization means, the opening formation means And a control means (7) for controlling a region in which the opening is formed, and the horizontal width of the opening formed in the peripheral portion of the region corresponding to one eye of the opening forming means is formed in the central portion. The opening is wider than the horizontal width of the opening.
[Selection] Figure 1

Description

  The present invention relates to an optical device for observation that can provide a stereoscopic image with less visual fatigue of an observer.

  Various systems have been proposed for displaying stereoscopic images by independently displaying binocular parallax images to the left and right eyes of an observer. Of these, a type of system in which some sort of image separation glasses is mounted in front of the left and right eyes of the observer and the observer performs binocular stereoscopic vision is generally called a “glasses-type stereoscopic display device”. Furthermore, it is also classified according to the separation method of the above-mentioned image separation glasses, the “anaglyph method” is used to separate the left and right eye images using color information, and the “polarized glasses method” is used to separate using polarized light. Called. In addition, the method of switching the left and right eye regions at high speeds and switching between the left and right eye regions at high speed and displaying the images for the left and right eyes in synchronism with this is called a “time-division shutter glasses method”.

  Patent Document 1 discloses an example in which, among the “time-division shutter glasses method”, a new technique for realizing “super multi-view display” and reducing visual fatigue is applied. “Super multi-view display” is a display method disclosed in Non-Patent Document 1, for example. In Non-Patent Document 1, if the parallax interval of a parallax image of a stereoscopic image is made so small that a plurality of parallax images are simultaneously incident on an observer's monocular, it is not realized in stereoscopic viewing using normal binocular parallax. It is said that the phenomenon of “eye adjustment and convergence during stereoscopic image observation” is realized. Moreover, it is said that this phenomenon may reduce visual fatigue of the observer. In Patent Document 1, in order to simultaneously enter a plurality of parallax images into an observer's monocular, a slit that can be displaced in time series within each spectacle frame in synchronization with a display unit that switches a plurality of parallax images at high speed. The image-separating glasses having the above are configured. Patent Document 1 discloses a technique for performing “super multi-view display” in which a plurality of parallax images are presented in a single eye using the image separation glasses, and allowing a viewer to perform natural stereoscopic vision. Yes.

JP 11-194299 A

Yoshihiro Kashiwagi: “3D display using super multi-view area”, Optical Technology Contact, 36, pp. 624-631 (1998)

  In order to enable an observer to observe an image with a wide angle of view in the invention of Patent Document 1, it is necessary to configure the above-described slit displacement range to cover from the central visual field to the peripheral visual field of the eyeball. However, when such a configuration is adopted, the number of slits increases, and as a result, the number of parallax images to be presented to the observer in synchronization with the formation of the slits also increases. In order to perform the above-mentioned “super multi-view display”, it is necessary to complete the series of operations of slit formation and parallax image presentation within the allowable time for afterimage of the observer. Accordingly, when the number of parallax images to be presented to the observer increases, the display unit that presents the parallax images accordingly requires image switching display at a higher frame rate. For example, when the number of slits is 10 per eye and 20 for both eyes, the frame rate required for the display unit is 20 times that of a normal display. It is not easy to prepare such a high-speed display.

  Therefore, the present invention performs super multi-view display that presents a plurality of parallax images within a single eye of an observer, reduces visual fatigue, and widens the angle of view and reduces the number of parallax images to be presented to the observer. Thus, an observation optical apparatus capable of keeping down the frame rate required for the display unit is provided.

  An observation optical apparatus according to one aspect of the present invention is an observation optical apparatus that allows a plurality of parallax images to be incident on one eye, the opening forming means capable of changing a region where an opening is formed, and the plurality of the plurality of parallax images. A signal synchronization unit that synchronizes the image display unit that displays parallax images in time series and the aperture formation unit, and a region in which the aperture of the aperture formation unit is formed is controlled based on a signal from the signal synchronization unit The horizontal width of the opening formed in the peripheral portion of the region corresponding to one eye of the opening forming means is wider than the horizontal width of the opening formed in the central portion. Features.

  According to the present invention, a super-multi-view display that presents a plurality of parallax images within a single eye of an observer is performed to reduce visual fatigue, and a wide angle of view and a low frame rate required for a display unit are suppressed. It is possible to provide an observation optical apparatus that can perform the above-described operation.

It is a top view of the optical apparatus for observation of this invention. It is a perspective view of the glasses for image separation of the present invention. It is a front view of the opening formed on the spatial modulator of the image separation glasses of the present invention. It is a figure which shows a mode that the position of the opening formed on the spatial modulator of the glasses for image separation of this invention changes in time series. It is a graph showing the visible light transmittance | permeability in the position of each opening of FIG. It is a graph showing the image display timing on the image display part of this invention. It is a figure for demonstrating the parallax image acquisition method. It is a figure which shows a mode that an observer observes the parallax image 2 through the opening of the area | region 2 using the image separation glasses of this invention. It is a figure which shows a mode that an observer observes the parallax image 3 through the opening of the area | region 3 using the glasses for image separation of this invention. It is a figure which shows the relationship with the light beam directivity when the width | variety of all the openings formed on the spatial modulator of the image separation glasses is unified into a small width. It is a figure which shows the relationship with the light beam directivity at the time of unifying all the width | variety of the opening formed on the spatial modulator of the spectacles for image separation into a large width | variety. It is a front view in case all the width | variety of the opening on the spatial modulator of the image separation glasses is unified.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a plan view of an observation optical apparatus according to an embodiment of the present invention. This apparatus has an image display unit 1 and image separation glasses 5 as main components. The image display unit 1 (image display unit) is connected to the image display unit control unit 3, converts an image signal transmitted therefrom to image information light, and displays the display image I on the screen. As will be described later, the image display unit 1 can display a plurality of parallax images in time series. The image display control unit 3 is also connected to the synchronization signal generation unit 4. The synchronization signal generation unit 4 generates a synchronization signal for image display, and a wireless synchronization signal is transmitted from the synchronization wireless signal transmission unit 9 (signal synchronization unit). To send.

  On the other hand, the image separation glasses 5 have the following configuration. Spatial modulators 6R and 6L (opening forming means) are provided in front of the eyeglass wearer (observer). Here, the spatial modulator for the right eye is described as 6R, and the spatial modulator for the left eye is described as 6L (hereinafter, “R” is similarly used for the right eye component, and "L" subscript is used.) These spatial modulators 6R and 6L can control a light transmitting region (hereinafter also referred to as a light transmitting region or an opening) and a non-transmitting region according to an input electric signal. It is driven by the spatial modulator driving units 7R and 7L (control means). The spatial modulators 6R and 6L are driven by the spatial modulator driving units 7R and 7L, so that the region where the opening is formed can be changed.

  Further, since it has a synchronization radio signal receiving unit 8 (signal synchronization means), it can receive the image display synchronization radio signal emitted from the synchronization radio signal transmission unit 9 and use this signal. Thus, the spatial modulators 6R and 6L can be driven synchronously. This synchronous drive will be described with reference to FIGS.

  FIG. 2 shows a state of a light transmission region formed on the spatial modulator 6R in the image separation glasses 5. The opening SL-6R has a slit shape that is narrow in the horizontal direction and long in the vertical direction, and a region other than the opening SL-6R is configured to block light. The opening SL-6R changes its formation position in time series in synchronization with the above-described synchronous radio signal.

  FIG. 3 is a view of the opening formation region observed from the front. The spatial modulators 6R and 6L can form slit openings at a plurality of positions, but in this embodiment, four left and right opening formation regions are formed, and the left and right openings are formed as time t passes. Control is performed so that only one region out of a total of eight regions is in a transmissive state.

  When one opening formation time is Δ, the regions 1 to 8 in FIG. 3 are sequentially in the transmission state, and the opening formation is completed at time 8Δ. This will be described in more detail with reference to FIG. In FIG. 4, when the time t = 0 to 1Δ, the region 1 is in a transmissive state, and the other regions are not transmissive. Similarly, the opening forming operation is repeated at a period of time 8Δ in the manner of only region 2 at time t = 1 to 2Δ, and only region 3 at time t = 2 to 3Δ. The visible light transmittance of each region is represented by a graph as shown in FIG. It is shown that the opening formation position is sequentially switched with the change of the time t on the horizontal axis of the graph.

  The width of the opening formed on the spatial modulators 6R and 6L varies depending on the region. This effect will be described in detail later. Here, first, synchronous display of opening formation and parallax image display will be described.

  In the present invention, control is performed to synchronize the timing of opening formation on the spatial modulators 6R and 6L and the timing of image display on the image display unit 1. FIG. 6 is a graph of image display timing on the image display unit 1. The parallax image 1 when the opening is formed in the region 1, the parallax image 2 when the opening is formed in the region 2, and the parallax image 3 when the opening is formed in the region 3. The parallax image display corresponding to the opening position is performed. In addition, since these series of opening formation cycles are all performed within the observer's afterimage allowable time (generally, within 1/60 seconds), the observer cannot recognize the displacement of the opening, and 4 and regions 5 to 8 are recognized as large openings. In other words, one period of sequential display of a plurality of parallax images and one period of sequential formation of apertures are both performed within the allowable afterimage time of the observer.

  Next, a method for acquiring the parallax images 1 to 8 will be described.

  FIG. 7 is an explanatory diagram of a parallax image acquisition method. In order to reproduce a good stereoscopic image, it is desirable to match the relative positional relationship between the space at the time of imaging and the space at the time of reproduction. That is, in the imaging space, the relative positional relationship between the object to be reproduced, the image display unit during reproduction, and the observer's viewpoint is virtually determined, and the imaging camera is arranged at the observer viewpoint position to image the object. To do. Thereafter, if trimming is performed within the screen range of the image display unit at the time of reproduction, an appropriate parallax image can be acquired.

  In the imaging space shown in FIG. 7, the virtual stereoscopic image display unit position is set to the position 1 ′ in the figure, and the virtual observer viewpoint positions are set to R1, R2, R3, R4, L1, L2, L3, and L4. ing. At this time, the observer viewpoints R1 to R4 and L1 to R4 correspond to the center points of the opening formation regions 1 to 8 of the spatial modulators 6R and 6L during image reproduction, respectively.

  Therefore, in order to acquire the parallax images 1 to 8 described above, the imaging cameras 31 may be arranged at the observer viewpoints R1 to R4 and L1 to 4, and the object 32 may be captured from each viewpoint position. However, since it is desirable that the image range displayed on the screen of the image display unit 1 at the time of reproduction coincides with the screen area of the virtual image display unit 1 ′ at the time of imaging, each parallax image is represented by a cross in the figure. Trimming limited to a common area with the space indicated by the hatched portion may be performed.

  If the eight parallax images obtained in this way are observed independently from the corresponding viewpoint positions, the observer can perform stereoscopic viewing. 8 and 9 are plan views of the present apparatus for explaining this situation. FIG. 8 shows a state at time t = 1 to 2Δ in FIGS. Of the regions of the spatial modulators 6R and 6L, only the region 2 is in a light transmitting state, and the observer can observe the display image I through the opening of the region 2, but at this time, the display image I includes the center of the region 2 A parallax image 2 acquired with the point R2 as a viewpoint is displayed. Similarly, at time t = 2 to 3Δ, only the region 3 is in a light transmission state as shown in FIG. 9, and the observer acquires the center point R3 of the region 3 through the opening of the region 3 as a viewpoint. The parallax image 3 is observed. When the above operation is repeated, the observer can observe the parallax images 1 to 8 independently through the openings in the regions 1 to 8.

  At this time, for example, the parallax images 1 to 4 are presented to the right eye and the parallax images 5 to 8 are presented to the left eye, and of these, a pair of one right eye parallax image and one left eye parallax image For example, by observing the parallax image 2 and the parallax image 6, the observer can perform stereoscopic vision by binocular parallax.

  Furthermore, the parallax images 1 to 4 are all displayed only on the viewer's right eye, and the parallax images 5 to 8 are all displayed only on the viewer's left eye almost simultaneously. The “multi-view display” state is achieved. As a result, the phenomenon of “matching of eye adjustment and convergence during stereoscopic image observation” is realized, and the visual fatigue of the observer is reduced.

  Next, the state change of “super multi-view display” due to the difference in the opening width will be described, and the device adopted by the present embodiment will also be described based on the change. FIGS. 10 and 11 are diagrams showing the state of the light beam incident on the observer's monocular when the width of the opening formed on the spatial modulator 6 is small and large in the configuration of this embodiment.

  In FIG. 10, the opening A is formed when the pixel A is displayed on the display image I, and the opening B is formed when the pixel B is displayed. Since the width of each aperture is set to be as small as that of the pixel, the light flux (indicated by hatching in the figure) that enters the observer's monocular through the aperture is a highly directional light flux. Since the above aperture formation and image display are all completed within the observer's allowable afterimage time, it appears to the observer that two light beams with high directivity are simultaneously incident on one eye. At this time, the two light beams intersect at the position of the intersection (1) in the figure, but the cross-sectional area of the intersection (1) is almost the same as the area of the pixel A and the pixel B because the directivity of the light beam is high. That is, it is difficult for the observer to specify where the light source surface of this light beam is. In this state, when the observer adjusts the eye lens 22 to change the focus of the eye, a double image is observed when focused on the image display surface Pi, but is focused on the intersection plane Pc. Sometimes it is recognized as one point image. For this reason, it is said that the adjustment of the observer's eyes is guided to the intersection plane Pc of the luminous flux.

  On the other hand, a case where the width of the opening is as large as several times the pixel as shown in FIG. 11 is compared with FIG. 10, and the light flux incident on the observer's monocular through each opening (displayed by shading in the figure) ) Is a diffused light beam having slightly lower directivity than in the case of FIG. At this time, the two light beams intersect at the position of the intersection (2) in the figure, but the cross-sectional area of the intersection (2) is larger than the areas of the pixels A and B because the directivity of the light beams is low. . In this state, when the observer adjusts the lens 22 of the eye to change the focus of the eye, the cross-sectional area of the light beam becomes larger when focused on the intersection plane Pc than when focused on the image display plane Pi. As perceived. Therefore, it can be estimated that the eye adjustment of the observer is more easily guided to the image display surface Pi as compared with the state of FIG.

  As described above, when the width of the opening formed on the spatial modulator 6 is smaller, the “matching of eye adjustment and convergence during stereoscopic image observation” state, which is an effect of super multi-view display, is more likely to occur. Conceivable.

  However, if the width of one opening is made smaller, the number of openings to be formed increases. This is because the opening forming area on the spatial modulator 6 must cover the angle of view through which the observer observes the display image I, so that the area of the opening forming range remains unchanged and the opening width becomes small. This is because it means that the number of divisions increases. Further, as described above, since the aperture formation cycle (= parallax image display cycle) should be performed within the allowable time for the afterimage of the observer, if the number of apertures to be formed increases, the image display unit 1 has a higher frame rate. The image must be displayed.

  Therefore, in the present embodiment, the width of the formed opening is set to be small in the “center visual field” of the observer's eye and large in the “peripheral visual field” to suppress the number of parallax images to be presented, and is required for the image display unit 1. The display frame rate is kept low. This is because, generally, the spatial resolution of the central visual field of the eye is higher, and it is said that the visual acuity is reduced to about 1/3 when the eye is shifted by 2 degrees from the eye gaze direction. “I thought it would be fine to give priority. In other words, in this example, a method is adopted in which a highly directional light beam is incident only on the “center visual field”, which is thought to contribute most to the depth perception of a stereoscopic image, and the directivity of the incident light beam is reduced in the “peripheral visual field”. ing. This method has already been shown in FIGS. The opening widths of the regions 2, 3, 6, and 7 corresponding to the positions immediately before the observer's left and right eyes are small, and the opening widths of the peripheral regions 1, 4, 5, and 8 are set large. As described above, the present invention provides the horizontal width of the opening formed in the regions 1 and 4 (5 and 8) in the peripheral portion of the regions 2 and 3 (6 and 7) corresponding to one eye of the spatial modulator 6. However, what is necessary is just to have a width | variety wider than the horizontal direction width | variety of the opening formed in the area | regions 2 and 3 (6, 7) of center part. Therefore, in the spatial modulator 6 of the present invention, as shown in FIG. 3, the horizontal width of the openings formed in the regions 1, 4 (5, 8) is formed in the regions 2, 3 (6, 7). It may be produced so as to have a physically wider width than the horizontal width of the opening. Alternatively, even when the horizontal widths of the openings formed in the regions 1 to 6 (7 to 12) have physically equal widths as shown in FIG. It may be controlled to have a wide width. That is, in the spatial modulator driving unit 7, the horizontal width of the openings formed in the regions 1, 2, 5, 6 (7, 8, 11, 12) in FIG. 12 is the regions 3, 4 (9, 10). What is necessary is just to control so that it may have a width | variety wider than the horizontal direction width | variety of the opening formed.

  It is confirmed that the performance required for the image display unit 1 is greatly different between when the present invention is applied and when it is not. For example, as shown in FIG. 12, when all the openings to be formed have the same width and 6 openings per eye and 12 openings for both eyes are formed, the frame rate required for the image display unit 1 is 12 times that of a normal display. . Since the display frame rate of a normal display is about 60 Hz, a display device with a display frame rate of 720 Hz is required to implement the invention of Patent Document 1. On the other hand, in the case of the present embodiment, as shown in FIG. 3, although the angle of view of the observer is the same as in FIG. 10, the numerical aperture to be formed is 4 per eye and 8 for both eyes. It has become. Therefore, the frame rate required for the image display unit 1 may be eight times that of a normal display, and can be realized with a display device having a display frame rate of about 480 Hz. That is, when the present invention is applied, the required frame rate can be reduced by about 33% as compared with the case where it is not.

  According to the structure of the said Example, the display frame rate requested | required of an image display part can be suppressed to a value lower than a prior art, keeping an observer's angle of view wide.

  Each embodiment described above is only a representative example, and various modifications and changes can be made to each embodiment in carrying out the present invention.

  The present invention can be used in all industrial fields that deal with stereoscopic images, especially for stereoscopic televisions, stereoscopic movies, industrial stereoscopic image display devices such as medical and design fields, and stereoscopic content screening at events and educational sites. Application is conceivable.

DESCRIPTION OF SYMBOLS 1 Image display part 4 Synchronization signal generation means 5 Glasses for image separation 6 Spatial modulator 7 Spatial modulator drive part 8 Synchronization radio signal receiving part 9 Synchronization radio signal transmission part

Claims (4)

An optical device for observation in which a plurality of parallax images are incident on one eye,
An opening forming means capable of changing a region in which the opening is formed;
A signal synchronization means for synchronizing the image display means for displaying the plurality of parallax images in time series and the opening forming means;
Control means for controlling a region in which the opening of the opening forming means is formed based on a signal from the signal synchronizing means;
An observation optical apparatus, wherein a horizontal width of an opening formed in a peripheral portion of a region corresponding to one eye of the opening forming means is wider than a horizontal width of an opening formed in a central portion.   The control means controls an area where the opening of the opening forming means is formed and a horizontal width of the opening based on a signal from the signal synchronization means, and corresponds to one eye of the opening forming means. The observation optical apparatus according to claim 1, wherein the horizontal width of the opening formed in the peripheral portion of the optical fiber is controlled to be wider than the horizontal width of the opening formed in the central portion.   The control means determines the horizontal width of the opening formed at the center of the area corresponding to one eye of the opening forming means among the horizontal widths of the openings formed in the opening forming means. The observation optical apparatus according to claim 2, wherein the width is set to be the same as a horizontal width of the pixel. 4. One cycle of the time-sequential sequential display of the plurality of parallax images and one cycle of the time-sequential sequential formation of the apertures are both within 1/60 seconds. The observation optical instrument according to any one of the above.