JP2006106426A - Image display device and imaging apparatus having the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make it possible to observe a highly precise image in an observing system for observing an image as a virtual image via an eyepiece optical system and also to miniaturize the entire image display device. <P>SOLUTION: The image display device includes a light source means 101, and a scanning means 105 by which a luminous flux from the light source means 101 modulated based upon image information is two-dimensionally scanned on predetermined faces. The image display device displays the two-dimensional image on the predetermined faces. The image display device has an optical path switching means 111 for switching between a first optical path by which the two-dimensional image formed on the first face 117 subjected to scanning is observed as a virtual image via the eyepiece optical system 109 and a second optical path by which the two-dimensional image formed on the second face 112 subjected to scanning is directly observed. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image display apparatus and an image pickup apparatus having the same, and is suitable for a finder apparatus used in, for example, a digital still camera, a video camcorder, and the like.

  Currently, in many digital cameras, video camcorders, and the like, an electronic view funder (hereinafter referred to as EVF) in which an observer looks into an electronic image displayed on a display element in order to confirm an image formed on an image sensor. Is included).

  As a display element for displaying an image, a two-dimensional display element called a so-called flat panel such as a transmissive liquid crystal element, a reflective liquid crystal element, or an organic EL element is used.

  The image displayed on the display element can be observed as a virtual image by the observer via the eyepiece optical system.

  Many techniques related to this EVF have been proposed.

  In recent years, EVFs are required to display higher definition images. In order to display a high-definition image on a flat panel, it is necessary to manufacture as many pixels as necessary. As a result, pixel defects increase by the number of pixels or the size of the flat panel increases. On the other hand, the size of the pixel becomes relatively small, and the manufacture becomes difficult.

  On the other hand, an image display apparatus that displays and observes an image using a scanning unit without using a two-dimensional display element has been proposed. (Patent Documents 1 and 2).

  In Patent Document 1, each color light of R, G, and B light-modulated based on image information is scanned in a horizontal direction and a vertical direction by a scanning unit, is incident on an eyeball through an optical system, and is directly imaged on the retina. Shows the technology to form.

  In the scanning type image display device disclosed in Patent Document 1, since it is required to scan light at a very high speed, a scanning unit such as a mirror that scans light has a very small and lightweight scanning unit. It is used. Such a scanning type image display apparatus is configured to scan light flux from the light source means and to light-modulate the light flux from the light source means in synchronism, as seen in a flat panel. Since there is no pixel, pixel defects do not occur in principle. Furthermore, since there is no boundary between pixels, a very high-definition image can be obtained.

  A semiconductor process is used to manufacture the scanning means used in such a scanning image display apparatus. In recent years, with the progress of semiconductor processes, micro electro mechanical system (MEMS) technology has been improved, and it has become possible to produce scanning means that can be operated at high speed while being small and light. As a scanning means for such MEMS technology, a manufacturing method using a semiconductor process has been proposed (Patent Documents 3 and 4).

  Also, MEMS technology is used as a two-dimensional scanning means for a head-mounted image display device (Non-patent Document 1).

On the other hand, in addition to EVF having an eyepiece optical system, current digital still cameras and the like attach flat panels (display elements) such as liquid crystal panels and organic EL panels attached to the camera body to the camera body. It is also configured so that an observer can observe an image by directly viewing the display element.
U.S. Pat. No. 5,467.104 US Pat. No. 5,701,132 Japanese Patent Application Laid-Open No. 07-175005 Japanese Patent Laid-Open No. 08-334723 SPIE Conference # 4407,19 (Jun 2001) Wafer scale packaging for a MEMS video scanner

  When the scanning image display device described in Patent Document 2 is used as an EVF for an imaging device such as a current digital camera or a video camcorder, a direct-view display panel and a display method attached to the camera body are used. The whole system becomes complicated because of differences.

  In general, when a scanning image display device is used in the finder system of an image pickup apparatus, there is a feature that high-definition image information can be observed.

  On the other hand, since recent imaging devices are reduced in size and weight, it is important to configure the entire image display device to be small when applied to the imaging device.

  According to the present invention, an EVF for observing an image as a virtual image via an eyepiece optical system and a direct-view display system for directly observing an image can be compatible with a single scanning unit, and an image display device having a simple configuration can be provided. For the purpose of provision.

The image display device of the present invention is
An image display apparatus that includes a light source unit and a scanning unit that two-dimensionally scans a light beam from the light source unit modulated based on image information on a predetermined surface, and displays a two-dimensional image on the predetermined surface. A first optical path for observing a two-dimensional image formed on the first scanned surface, which is a predetermined surface, as a virtual image through the eyepiece optical system, and a second optical surface formed on the second scanned surface, which is the predetermined surface. And a second optical path for directly observing the two-dimensional image to be observed.

  According to the present invention, a so-called EVF and a direct-view display system can be compatible with a single scanning unit, and an image display apparatus having a simple configuration can be obtained.

  FIG. 9 is a schematic diagram of the configuration of the scanning means in the image display apparatus of the present invention. FIG. 9 shows how the light beam 103 light-modulated based on the image information from the light source means 101 is scanned on the scanned surface 137 by the scanning means 105 to form image information two-dimensionally.

  As shown in FIG. 9, the coordinate axis is the X axis in the plane of the deflecting surface (deflecting / reflecting mirror) 133 of the optical scanning unit 105, the vertical direction is the Y axis, and the normal direction to the deflecting surface 133 is Z. Axis.

  The deflection surface 133 is provided with a torsion bar 132 for swinging in the X-axis direction and a torsion bar 131 for swinging in the Y-axis direction, thereby forming a gimbal structure. Although the deflection surface 133 is driven to swing, the X axis and the Y axis are hereinafter referred to as the rotation axes of the deflection surface 133, respectively.

  These torsion bars 131 and 132 are supported by a support base 130. With respect to the X-axis direction (horizontal direction), the deflection surface 133 is driven by an actuator using electromagnetic force, electrostatic force, etc. (not shown), and the deflection angle of the reflection surface of the deflection surface 133 is caused by the torsional resonance action of this structure. Change and scan the light.

  The Y-axis direction (vertical direction) is controlled so as to be synchronized with the X-axis direction so that the light beam 103 draws a sawtooth or triangular wave locus on the scanned surface 137 by an actuator (not shown). Driven. In FIG. 9, a line La1 shows an example of a forward scanning line in a horizontal direction by a swinging operation, and a line La2 shows an example of a return path. Actually, the number of scanning lines is larger than that in FIG. 9, but is shown in a thinned form for easy understanding.

  In FIG. 9, a light beam 103 modulated with image information from the light source unit 101 is incident on a deflection surface (reflection mirror) 133 of the scanning unit 105 via a condenser lens 104. The deflecting surface 133 reflects the incident light beam. The deflection surface 133 swings around the torsion bars 131 and 132 and deflects the light beam 103 by tilting the deflection surface 133. The light beam 103 is condensed on a predetermined surface (scanned surface) 137, and the light from the light source means 101 is two-dimensionally scanned on the surface 137 as the deflection surface 133 is inclined. Become. Reference numerals 134 and 136 show examples of scanning lines on the surface to be scanned 137, and this scanning type image display apparatus performs raster scanning on the surface to be scanned 137. A line 134 represents an example of a horizontal scanning line in raster scanning, and a line 136 represents a return line. By synchronizing the timing of this raster scan and the modulation of the light beam emitted from the light source means 101, a desired image is displayed in the effective area 135 in the scanned surface 137.

  The support substrate 130 is made of, for example, a Si substrate, and a metal reflection film and a dielectric reflection film are formed on the deflecting surface 133 so as to reflect an incident light beam with high reflectance.

  For driving the scanning means 105, an electromagnetic actuator (not shown), an electrostatic actuator, or the like manufactured on the Si substrate 130 by a semiconductor process is used.

  In FIG. 9, the light source unit 101 is shown as one light source. However, a plurality of light source units are used, for example, light of red, blue, and green colors are combined and each is synchronized with the scanning unit independently. It is also possible to display a color image by modulating while taking the image.

  FIG. 1 is a main part schematic diagram of Embodiment 1 when the image display apparatus of the present invention is applied to a finder system of an imaging apparatus such as a video camera or a digital camera.

  FIG. 2 is a schematic view of the main part when the optical path is switched by the optical path switching means 111 in FIG.

  In the image display apparatus according to the first embodiment, the observer directly views the first observation system for observing the image scanned and displayed on the scanned surface 117 as a virtual image and the image scanned and displayed on the screen 112. It has a second observation system for observation, and each display is realized by a scanning type image display apparatus having the configuration shown in FIG.

  FIG. 1 is a cross-sectional configuration in the vertical scanning direction (Y direction), and shows a first of a first observation system in which an observer observes an image displayed on a scanned surface 117 as a virtual image via an eyepiece optical system 109. The optical path is shown.

  FIG. 2 shows a second optical path through which an observer directly observes image information on the screen 112.

  The light source means 101 includes light emitting diodes (LEDs) 101r, 101g, and 101b that emit light in the wavelength bands of red, green, and blue, and the LEDs 101r, 101g, and 101b are independently provided by a light source driving circuit 101d. Light modulated.

  The light beam from the light source means 101 is color-combined by the color-combining optical system 102 and bundled into one beam 103 and becomes condensed light via the condensing optical system 104. The light beam emitted from the condensing optical system 104 is incident on the optical scanning unit 105 having the configuration shown in FIG. 9, and is reflected and deflected by a deflection reflection mirror (deflection surface) provided at the deflection point 105c.

  The optical scanning unit 105 is a two-dimensional scanning unit capable of raster scanning an incident light beam in a two-dimensional direction as shown in FIG. 9, and an image 107 of the light source unit 101 is formed on the scanned surface 117 by the condensing optical system 104. Then, raster scanning is performed on the surface 117.

  Reference numerals 107a, 107b, and 107c denote light source images based on the light beams 106a, 106b, and 106c from the LEDs 101r, 101g, and 101b that are formed by scanning on the surface to be scanned 117, respectively.

  The optical scanning unit 105 is connected to the optical scanning unit driving circuit 105d. The optical scanning unit driving circuit 105d and the light source driving circuit 101d are connected to a scanning image display device and a control circuit 115 for controlling the whole, and are controlled in synchronism so as to display a desired video.

  As a result, the two-dimensionally scanned image information is displayed on the scanned surface 117.

  The observer observes an image formed on the scanned surface 117 through the eyepiece optical system 109 at the position of the observer's eye 110.

  In this embodiment, the reflecting mirror 108 is disposed in the eyepiece optical system 109 to bend the optical path. In this configuration, conjugate images corresponding to the light source images 107a, 107b, and 107c on the scanned surface 117 are formed on the retina 116 of the observer's eye 110 as conjugate points 114a, 114b, and 114c. As a result, the observer recognizes the scanned image formed on the retina 116.

  Between the optical path of the scanning means 105 and the surface to be scanned 117, a rotatable optical path switching / switching means 111 is provided. The optical path switching / switching means 111 is attached to the optical path switching / switching means driving unit 111m. The optical path switching means driving unit 111m is configured to be driven by the optical path switching means driving circuit 111d so as to switch between the first optical path shown in FIG. 1 and the second optical path shown in FIG. In the present embodiment, the same number indicates the same function, and the description is omitted.

  FIG. 2 is a configuration diagram when an image is displayed on the screen 112. The light path switching means 111 has a reflection surface 111r formed on one surface, which reflects the scanning light beam and deflects the light path in the direction of the transmissive screen 112.

  On the screen 112, light source images (image information) scanned by 107a ', 107b', 107c 'corresponding to the light source images 107a, 107b, 107c in FIG. 1 are formed.

  The screen 112 has a diffusing action, and the observer directly observes the image formed on the screen 112 at the position of the eye 110 of the observer.

  Further, a light shielding unit 113 is attached in the vicinity of the screen 112 and is driven by the light shielding unit driving circuit 113d. When the image is observed through the first optical path shown in FIG. It is configured so that light from the outside can be shielded.

  When the image is observed through the second optical path shown in FIG. 2, the light shielding means 113 is retracted below the camera so as not to obstruct the optical path.

  The light shielding unit 113 is driven and controlled by the image display device control circuit 115 so as to move in conjunction with the operation of the optical path switching unit 111.

  With the configuration of the present embodiment, the optical path switching unit 111 is arranged in the scanning image display device, so that the observer observes the image on the scanned surface 117 as a virtual image, and the observer has a screen. The second optical path for direct observation of the image on 112 can be switched, and two display formats are realized by one scanning means 105.

  FIG. 5A shows a first optical path for displaying an image by scanning in the first embodiment, and FIG. 5B shows a second optical path for displaying an image by scanning.

  5A and 5B, the optical path is developed and described for easy understanding. The fifth (A) optical scanning means 105 is a reflection type optical scanning means, but is developed and described in this figure.

  In the case of the first optical path in which the observer in FIG. 5A observes the image as a virtual image, the luminous efficiency of the light source 101 is high because the eyepiece optical system 109 directs the light beam toward the observer's pupil 110a. . When observing through the first optical path, since the image is observed as a virtual image, the apparent field of view can be increased and an image with high resolving power can be recognized.

  In the case of observing an image through the second optical path in FIG. 5B, a larger amount of light from the light source is required for direct observation of the light diffused by the transmissive screen 112. Therefore, the condensing optical system 104 is interlocked with the switching of the optical path, and the imaging magnification with respect to the position of the surface to be scanned 117 with respect to the light source means 101 is set higher than in the case of the first optical path in FIG. The condensing optical system 104 is driven in the optical axis direction by the moving means 104 so that more light is collected on the transmission screen 112.

  Further, the brightness on the screen surface may be adjusted by adjusting the output from the light source means by using the light amount adjusting means for adjusting the brightness on the screen surface in conjunction with the optical path switching means.

  In FIG. 1 and FIG. 2, a moving means 104m for the condensing optical system 104 and a drive circuit 104d (imaging magnification changing means) are connected so that the condensing optical system 104 can be moved in conjunction. By moving the condensing optical system 104 in the direction of the optical axis in conjunction with the optical path switching means 101, it is possible to display an image with an imaging magnification adapted to the first and second optical paths.

  6 (A) and 6 (B) are schematic views of other embodiments in FIGS. 5 (A) and 5 (B). In FIG. 6, the second optical path switching means 118 is arranged between the optical scanning means 105 and the light source means 101, and the first optical path in FIG. 6 (A) and the second optical path in FIG. 6 (B). This is an example in which the image can be displayed by the light flux from the light source means adapted to each of them in conjunction with the switching of. For example, in the case of the first optical path in FIG. 6A in which an observer observes an image as a virtual image, the image is displayed by the light source 101 having a relatively low output. On the other hand, as shown in FIG. 6B, when an image is displayed directly by the observer, the image is displayed by the light flux from the light source means 101 'having a relatively high output. At this time, condensing optical systems 104 and 104 'having different powers adapted to the respective optical paths are arranged. In FIG. 6A, the eyepiece optical system 109 is omitted.

  FIG. 3 is a schematic diagram of another embodiment in the second optical path (corresponding to FIG. 2) in the first embodiment.

  An optical element 112f such as a Fresnel lens having a condensing function is disposed in the vicinity of the transmission screen 112 so as to guide diffused light toward the observer's eye 110. With this configuration, it is possible to increase the light use efficiency in the second optical path.

  FIG. 4 is a schematic diagram of a digital camera 120 on which the scanning image display apparatus according to the first embodiment is mounted. The subject 121 is photographed on a solid-state image sensor (not shown) via the lens unit 122. The user can select and observe the image by using the electronic viewfinder 125 for observing the output image from the solid-state imaging device as a virtual image or the finder 124 for viewing the image on the screen directly. It becomes. A finder switching setting unit (not shown) can be used to set which finder to display. For example, a switch may be attached to the digital camera 120 so that the finder switching setting may be performed, or the electronic viewfinder 125 may be detected and switched to detect it.

  In the first embodiment, as shown in FIG. 4, the observation of the images by the first and second optical paths is arranged vertically with respect to the camera body. However, the present invention is not limited to this, and the horizontal direction It may also be in the diagonal direction.

  FIG. 7 is a schematic diagram of a main part of an image display device according to a second embodiment of the present invention, and FIG. 8 is a schematic diagram of the main part when the optical path is switched by the optical path switching means 211 in FIG. The present embodiment is different from the first embodiment in that the optical path switching means 211 also serves as a light blocking function.

  The image display apparatus according to the second embodiment is a finder apparatus such as a digital camera, and includes a first observation system (FIG. 7) for observing an image formed on the surface to be scanned 217 as a virtual image, and an observer screen 212. It has a second observation system (FIG. 8) for directly observing the upper image, and each display is realized by a scanning image display device having the configuration shown in FIG.

  FIG. 7 is a cross-sectional configuration in the vertical scanning direction, and shows a first optical path of a first observation system in which an observer observes an image formed on the surface to be scanned 217 as a virtual image. It corresponds to.

  FIG. 8 shows a second optical path through which the observation system observes an image on the screen 212, and corresponds to FIG.

  The light source unit 201 includes light emitting diodes (LEDs) 201r, 201g, and 201b that emit light in the red, green, and blue wavelength bands, and each of the LEDs 201r, 201g, and 201b is independently changed by a light source driving circuit 201d. It is adjusted.

  The light beam from the light source means 201 is constituted by the color synthesis optical system 202 and bundled into one beam 203, and becomes focused light through the condensing optical system 204. The light beam emitted from the condensing optical system 204 enters the optical scanning unit 205 having the configuration shown in FIG. 9, and is reflected and deflected by the deflection mirror provided at the deflection point 205c.

  The optical scanning unit 205 is a two-dimensional scanning unit capable of raster scanning an incident light beam in a two-dimensional direction as shown in FIG. 9, and an image 207 of the light source unit 201 is formed on the scanned surface 217 by a condensing optical system. Then, raster scan of the surface 217 is performed. Reference numerals 207a, 207b, and 207c represent light source images based on the light beams 206a, 206b, and 206c from the LEDs 201r, 201g, and 201b that are formed by scanning on the scanning surface 217.

  The optical scanning unit 205 is connected to the optical scanning unit driving circuit 205d. The optical scanning unit driving circuit 205d and the light source driving circuit 201d are connected to a control circuit 215 that controls the entire scanning image display apparatus, and are controlled in synchronization to display a desired video. As a result, a two-dimensionally scanned image is displayed on the scanned surface 217.

  The observer observes the image formed on the scanned surface 217 via the eyepiece optical system 209 at the position of the eye 210 of the observer.

  In this embodiment, the reflecting mirror 208 is disposed in the eyepiece optical system 209 to bend the optical path. In this configuration, conjugate images corresponding to the light source images 207a, 207b, and 207c on the scanned surface 217 are formed as conjugate points 214a, 214b, and 214c on the retina 216 of the observer's eye 210. As a result, the observer recognizes the scanned image formed on the retina 216.

  A rotatable optical path switching unit 211 is provided between the optical path of the scanning unit 205 and the surface to be scanned 217. The optical path switching unit 211 is configured such that the optical path switching unit driving unit 211m is driven by the optical path switching unit driving circuit 211d and can switch between the first optical path shown in FIG. 7 and the second optical path shown in FIG. ing. In the case of displaying on the second optical path, the optical path switching unit 211 operates to reflect the scanning light beam by the reflecting surface 211r formed on the optical path switching unit 211, and the light source image 207a, FIG. The scanned light source images of 207a ′, 207b ′, and 207c ′ corresponding to 207b and 207c are displayed. The transmissive screen 217 has a diffusing action, and the observer directly observes an image formed on the transmissive screen 212 with the eyes 210 of the observer.

  As described above, in this embodiment, the light blocking means 113 in the first embodiment also functions as the optical path switching means 211.

  The condensing optical system 204 is connected to a moving unit 204m for driving the condensing optical system and a drive circuit 204d for controlling the moving unit 204m, and in conjunction with the optical path switching unit 211, the light amount and the surface to be scanned 217 or the screen. The imaging magnification of the light source image (image) on 212 is appropriately set.

  Further, the brightness on the screen surface may be adjusted by adjusting the output from the light source means by using the light amount adjusting means for adjusting the brightness on the screen surface in conjunction with the optical path switching means.

  Further, the light source means may be switched as in FIG. 6 in the first embodiment.

  Further, by arranging a Fresnel lens or the like on the transmission screen 212 as shown in FIG. 3 of the first embodiment, the observation image in the second optical path can be brightened.

  Although the second embodiment is described as a finder of a digital camera, the same effect can be obtained even with a finder such as a digital video.

  In the second embodiment, an optical system is not disposed between the scanned surface 217 and the scanning optical system 205. However, the configuration of the optical system is not particularly limited, and a light beam scanned by the scanning unit 205 is used. If the optical path switching means 212 can be switched, two displays can be performed.

  Further, in the second embodiment, a transmissive screen having a diffusing action is used as a screen for an observer to look directly at. However, a reflective screen can be used as long as the observer can directly view. The effect is obtained.

  As described above, according to each embodiment, by using the optical path switching means, an electronic viewfinder for observing an electronic image formed by scanning on the surface to be scanned as a virtual image, and on the surface to be scanned It is possible to select and use a finder for directly observing the electronic image formed on the screen. Further, an observation system can be obtained in which the light amount and the resolution of the image can be set to a state appropriate for each observation state.

Schematic view of the main part showing the optical path of the first observation system of Example 1 of the present invention. Schematic view of the main part showing the optical path of the second observation system of Example 1 of the present invention Explanatory drawing which shows the other form of Example 1 of this invention. 1 is a schematic diagram of an imaging apparatus using an image display apparatus according to a first embodiment of the present invention. Schematic of the condensing optical system of Example 1 of the present invention Schematic of the other form of the condensing optical system of Example 1 of this invention Schematic view of the main part showing the optical path of the first observation system of Example 2 of the present invention. Schematic view of the main part showing the optical path of the second observation system of Example 2 of the present invention. Schematic diagram of an optical scanning device used in an embodiment of the present invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Light source means 102 Color composition optical system 103 Light beam 104 Condensing optical system 105 Optical scanning means 106 Scanning light beam 107 Scanning light source image 108 Deflection mirror 109 Eyepiece optical system 110 Eye of an observer 111 Optical path switching means 112 Transmission type screen 113 Light shielding means 114 Retina Image 115 Scanning Display Device Driving Circuit 116 Retina 117 Scanned Surface 120 Camera (Imaging Device)
121 Subject 122 Lens portion 123 Shutter 124 Finder 125 Electronic viewfinder 130 Optical scanning means substrate 131 Vertical torsion bar 132 Horizontal torsion bar 133 Deflection surface 134 Scan line 135 Effective area 136 Return scan line 201 Light source 202 Color synthesis optical system 203 204 Condensing optical system 205 Optical scanning means 206 Scanning light beam 207 Scanning light source image 208 Deflection mirror 209 Eyepiece optical system 210 Eye of observer 211 Optical path switching means 212 Transmission type screen 213 Light shielding means 214 Retina image 215 Scanning display device drive circuit 216 Retina

Claims (6)

  An image display device having light source means and scanning means for two-dimensionally scanning a light beam from the light source means modulated based on image information on a predetermined surface, and displaying a two-dimensional image on the predetermined surface A first optical path for observing a two-dimensional image formed on the first scanned surface, which is the predetermined surface, as a virtual image through the eyepiece optical system, and on the second scanned surface, which is the predetermined surface An image display device comprising: an optical path switching means for switching between a second optical path for directly observing a two-dimensional image formed on the optical display.   2. An image display device according to claim 1, further comprising a light amount adjusting means for changing the brightness of each two-dimensional image between the first optical path and the second optical path in conjunction with the operation of the optical path switching means. .   3. The image display device according to claim 1, further comprising an imaging magnification changing unit that changes an imaging magnification of each two-dimensional image between the first optical path and the second optical path.   2. A light shielding unit for suppressing external light from entering from the second scanned surface side in a state where the first optical path is formed by the optical path switching unit. 4. The image display device according to any one of items 3.   The optical path switching means in a state in which the first optical path is formed suppresses the incidence of external light from the second scanned surface, and also serves as the light shielding means. 4. Image display device.   An imaging apparatus comprising: an imaging system; and the image display apparatus according to claim 1, wherein image information obtained by the imaging system is observed using the image display apparatus.