WO2017014317A1 - Dispositif de projection - Google Patents

Dispositif de projection Download PDF

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Publication number
WO2017014317A1
WO2017014317A1 PCT/JP2016/071624 JP2016071624W WO2017014317A1 WO 2017014317 A1 WO2017014317 A1 WO 2017014317A1 JP 2016071624 W JP2016071624 W JP 2016071624W WO 2017014317 A1 WO2017014317 A1 WO 2017014317A1
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WO
WIPO (PCT)
Prior art keywords
projection
optical system
lens group
optical path
imaging
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PCT/JP2016/071624
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English (en)
Japanese (ja)
Inventor
佐野永悟
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コニカミノルタ株式会社
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Publication of WO2017014317A1 publication Critical patent/WO2017014317A1/fr

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    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B13/00—Optical objectives specially designed for the purposes specified below
    • G02B13/16—Optical objectives specially designed for the purposes specified below for use in conjunction with image converters or intensifiers, or for use with projectors, e.g. objectives for projection TV
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B13/00—Optical objectives specially designed for the purposes specified below
    • G02B13/18—Optical objectives specially designed for the purposes specified below with lenses having one or more non-spherical faces, e.g. for reducing geometrical aberration
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B17/00—Systems with reflecting surfaces, with or without refracting elements
    • G02B17/08—Catadioptric systems
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B17/00—Details of cameras or camera bodies; Accessories therefor
    • G03B17/48—Details of cameras or camera bodies; Accessories therefor adapted for combination with other photographic or optical apparatus
    • G03B17/54—Details of cameras or camera bodies; Accessories therefor adapted for combination with other photographic or optical apparatus with projector
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B21/00—Projectors or projection-type viewers; Accessories therefor
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B21/00—Projectors or projection-type viewers; Accessories therefor
    • G03B21/14—Details
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N5/00—Details of television systems
    • H04N5/74—Projection arrangements for image reproduction, e.g. using eidophor

Definitions

  • the present invention relates to a projection apparatus capable of projecting and capturing an image, and more particularly to a projection apparatus capable of capturing a wide angle.
  • a projection apparatus that enlarges and projects an image displayed on an image display element onto a screen by a projection optical system is desired to have a wide-angle projection optical system that can be projected on a large screen even at a short projection distance while being small and light. Yes. Under such circumstances, short-focus projectors that can be arranged at positions close to the screen, such as directly below or directly above the screen, have appeared.
  • the projector can also project the PC screen onto a whiteboard or the like while writing handwritten characters on the screen and recording the information as an image with an imaging optical system.
  • projectors generally require various correction processes such as trapezoidal distortion correction of projected images and brightness correction according to the surrounding environment. If only trapezoidal distortion correction, brightness correction, or simple human motion detection is required, the imaging optical system needs only about VGA pixels, but handwritten characters are superimposed on the projected image, and the image data In order to capture the image, it is necessary to have a mega-class resolution, and it is desired that the imaging lens used for it has high performance.
  • an imaging optical system when an imaging optical system is to be incorporated in a short focus projector arranged at a position close to the screen as described above, the imaging lens needs to have a very wide angle. For this reason, it is difficult to ensure sufficient resolution at the periphery of the projection surface, and since distortion at the periphery is large, image processing such as distortion correction is performed on the captured image, resulting in resolution at the periphery. It will cause a decline. Therefore, there is a need for an optical system that suppresses as much as possible the barrel-shaped distortion that tends to occur in a wide-angle lens while having an ultra-wide angle.
  • the projection optical system can be used as it is as the imaging optical system
  • the apparatus itself can be downsized rather than mounting the imaging optical system separately from the projection optical system, and the resolution is high and the distortion is low. A photographed image can be obtained.
  • the imaging optical system has a wider angle of view than the projection optical system.
  • the optical system is exactly the same in the projection optical path and the imaging optical path, and therefore, when the image display element and the imaging element are the same size, the angle of view is For example, a character written outside the projected image cannot be captured.
  • the angle of view of the projection optical system is set wider than the projection range, and an imaging element having a larger area than the image display element is disposed. Therefore, problems such as an increase in the size and cost of the optical system and thus the apparatus arise.
  • the image display element and the image sensor are arranged at very close positions, there is a high risk that light from the illumination optical system incident on the image display element will be incident on the image sensor as stray light. It becomes a component and becomes a factor of deteriorating the captured image.
  • Patent Document 2 a projection optical system is commonly used by separating a projection-side optical path and an imaging-side optical path by a TIR prism disposed between an image display element and the projection optical system.
  • An optical system capable of obtaining an imaging means has been proposed.
  • An embodiment in which a magnification correction optical system is disposed between the TIR prism and the image sensor in order to make the projection field angle and the imaging field angle different is also disclosed.
  • magnification correction optical system since the optical path length in the TIR prism on the imaging side is longer than that on the projection side, a light beam forms an image once inside the TIR prism in the optical path on the imaging side. Therefore, although the details of the magnification correction optical system are not mentioned in the optical system of Patent Document 2, the magnification correction optical system needs to be a re-imaging relay optical system, and the degree of design difficulty is high. Will also increase.
  • JP 2003-44839 A Japanese Patent No. 5174273
  • An object of the present invention is to provide a small-sized projection device equipped with an imaging lens having an imaging field angle wider than the projection field angle and an ultra-wide angle.
  • a projection apparatus is a projection apparatus having a projection optical system that magnifies and projects an image obtained from an image display element illuminated by illumination light onto a projection plane.
  • An optical path separation element for separating the optical path is arranged at a position different from the optical path part of the illumination light inside the optical system, and the light from the projection surface is separated in a direction different from the optical path of the projection optical system by the optical path separation element.
  • An image sensor is disposed on the optical path, and lens groups having different refractive powers are disposed between the optical path separation element and the image display element, and between the optical path separation element and the image sensor, respectively, and are more than the projection field angle. Wide field of view.
  • an optical path separation element for separating an optical path is disposed inside the projection optical system, thereby projecting a part of the projection optical system (a lens group disposed on the projection plane side from the optical path separation element). Since it can be used in common for imaging, it is possible to reduce the number of parts compared to mounting the imaging optical system separately from the projection optical system, and as a result, it is possible to reduce the size of the projection apparatus. Further, by arranging the optical path separation element at a position different from the optical path portion of the illumination light, stray light caused by the illumination light can be suppressed, and a captured image with good image quality with reduced flare can be obtained.
  • the lens group between the image display element and the optical path separation element and between the optical path separation element and the imaging element, in the vicinity of the optical path separation element after emitting the optical path separation element on the imaging optical path. Since it is not necessary to use a re-imaging optical system for forming an image, the entire optical system can be simplified and reduced in size.
  • the imaging optical system can have a peripheral resolving power equivalent to that of the projection optical system and has little distortion. Further, by arranging lens groups having different refractive powers between the image display element and the optical path separation element and between the optical path separation element and the imaging element, respectively, the imaging field angle is made wider than the projection field angle, thereby projecting.
  • FIG. 1 is a cross-sectional view of an imaging optical system according to Example 1.
  • FIG. 5A and 5B are MTF characteristic diagrams showing performance on the projection surface of the projection optical system of Example 1.
  • FIG. 6A and 6B are MTF characteristic diagrams showing performance on the imaging surface of the imaging optical system of Example 1.
  • FIG. 7A and 7B are diagrams for explaining the MTF evaluation points on the projection plane or the imaging plane. 6 is a cross-sectional view of a projection optical system of Example 2.
  • FIG. 6 is a cross-sectional view of an imaging optical system according to Example 2.
  • FIG. 10A and 10B are MTF characteristic diagrams showing the performance of the projection optical system of Example 2 on the projection surface.
  • 11A and 11B are MTF characteristic diagrams showing performance on the imaging surface of the imaging optical system of Example 2.
  • FIG. 1 shows a projection apparatus incorporating a projection optical system according to an embodiment of the present invention
  • FIG. 2 shows a projection state by the projection optical system.
  • the projection apparatus 100 also enables imaging when projecting an image, and includes a projection optical system 10, an illumination optical system 20, a polarization beam splitter 30, a reflective liquid crystal element 40, an image drive circuit 41,
  • the imaging optical system 50, the imaging device 60, the parallel plate F2, the imaging drive circuit 61, the image processing unit 62, and the control circuit 80 are included.
  • the projection device 100 also has a function as an imaging device for a part of the configuration.
  • the projection apparatus 100 of the present embodiment is disposed directly below the projection body SB shown in FIG. 2, that is, the projection plane SC.
  • the projection optical system 10 enlarges an image obtained from the reflective liquid crystal element 40 that is an image display element and projects it on a screen or other projection body SB.
  • the projection optical system 10 includes a polarization beam splitter 30, a first lens group 11, an optical path separation element 91, a third lens group 92, and a reflection optical system 70 in order from the reflective liquid crystal element 40 side.
  • the optical path separation element 91, the third lens group 92, and the reflection optical system 70 are used in common with the imaging optical system 50 described later. Focusing can be performed by moving some of the first lens group 11 or the third lens group 92 or the entire lens group in the direction of the optical axis OA.
  • the third lens group 92 enables focusing that is common to the imaging optical system 50.
  • the first lens group 11 includes, in order from the reflective liquid crystal element 40 side, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, and a fifth lens L5. And a sixth lens L6.
  • the first lens group 11 includes at least one aspheric lens.
  • an aperture stop ST is provided between the sixth lens L6 and the optical path separation element 91.
  • the illumination optical system 20 includes a light emission source, a condensing optical system, a polarization conversion element, and the like, although detailed description is omitted.
  • the light source for example, a light source incorporating three color LEDs or the like can be used, and the condensing optical system converts, for example, illumination light from the three color LEDs or the like into substantially parallel light.
  • the polarization conversion element converts the incident light into specific polarization without reducing the amount of incident light.
  • the polarization beam splitter (PBS) 30 is formed by bonding a pair of right-angle prisms, and reflects linearly polarized light in a predetermined direction incident from the illumination optical system 20 on the inclined surface of the one right-angle prism on the bonding surface.
  • a polarization separation surface 31 made of a polarization separation film is formed.
  • the polarization beam splitter (PBS) 30 is disposed in the optical path portion of the illumination light, reflects the illumination light emitted from the illumination optical system 20, and makes it incident on a reflective liquid crystal element 40 described later. Further, the modulated light emitted from the image display surface DD of the reflective liquid crystal element 40 is transmitted and incident on the first lens group 11.
  • the reflective liquid crystal element 40 is a display element (image display element) that forms image light, and can be said to be a light modulation element in that image light is formed from illumination light by changing a spatial reflectance.
  • the reflective liquid crystal element (image display element) 40 is an image display panel that is a plate-like electronic component.
  • the reflection type liquid crystal element 40 is a micro display also called LCOS (Liquid crystal on silicon), in which a circuit is directly formed on the surface of a silicon chip and a liquid crystal layer is sandwiched between a counter substrate. When a voltage corresponding to a drive signal is applied to a liquid crystal layer for each pixel, the reflective liquid crystal element 40 modulates illumination light by changing the arrangement of liquid crystal molecules and displays a desired image. .
  • the image driving circuit 41 is a circuit portion that operates the reflective liquid crystal element 40 based on an image signal.
  • the image drive circuit 41 operates based on a control signal from a control circuit 80 described later, and outputs a drive signal corresponding to the image signal to the reflective liquid crystal element 40 to perform an image display operation.
  • the imaging optical system 50 reduces the image of the projection surface SC and its periphery (rectangular outer region) and forms it on the image sensor 60.
  • the imaging optical system 50 includes a parallel plate F2, a second lens group 51, an optical path separation element 91, a third lens group 92, and a reflection optical system 70 in order from the imaging element 60 side.
  • the optical path separation element 91, the third lens group 92, and the reflection optical system 70 are used in common with the projection optical system 10. Focusing can be performed by moving some of the second lens group 51 or the third lens group 92 or the entire lens group in the direction of the optical axis OA.
  • the second lens group 51 includes, in order from the image sensor 60 side, a twelfth lens L12, a thirteenth lens L13, a fourteenth lens L14, a fifteenth lens L15, a sixteenth lens L16, And a seventeenth lens L17.
  • the second lens group 51 includes at least one aspheric lens.
  • an aperture stop ST is provided between the seventeenth lens L17 and the optical path separation element 91.
  • the first and second lens groups 11 and 51 which are lens groups having different refractive powers, between the optical path separating element 91 and the reflective liquid crystal element 40 and between the optical path separating element 91 and the imaging element 60, respectively.
  • the imaging field angle is wider than the projection field angle.
  • the image sensor 60 is a CMOS image sensor that detects a projected image.
  • the image sensor 60 is disposed on an optical path in which the light beam from the projection surface SC is separated in a direction different from the optical path of the projection optical system 10 by the optical path separation element 91.
  • An image formed by the imaging optical system 50 is formed on the imaging surface IS which is a photoelectric conversion unit of the imaging element 60. That is, an image on the whiteboard or other projection body SB is reduced and formed on the imaging surface IS of the imaging device 60.
  • the image pickup device 60 is not limited to the above-described CMOS type image sensor, and may be one to which another device such as a CCD is applied.
  • the imaging surface IS which is the light receiving surface of the imaging element 60, has a rectangular shape similar to the image display surface DD of the reflective liquid crystal element 40, and has an area equal to or less than that of the image display surface DD. Thereby, size reduction and cost reduction of the projection apparatus 100 can be achieved.
  • the image pickup drive circuit 61 outputs an image to the image pickup device 60 by outputting YUV or other digital pixel signals to an external circuit or receiving a voltage or a clock signal for driving the image pickup device 60 from the control circuit 80.
  • the detection operation is performed.
  • the imaging drive circuit 61 performs a focusing operation by the first and second lens groups 11 and 51 and other lens groups.
  • the image processing unit 62 can perform image processing such as color correction, gradation correction, and compression on the imaging data obtained by using the imaging drive circuit 61, and stores the acquired imaging data or processed data. You can also. Further, the image processing unit 62 corrects the trapezoidal distortion of the projection image acquired by the image sensor 60. The image processing unit 62 performs distortion correction processing on the image signal based on lens correction data read from a data storage unit (not shown).
  • the reflection optical system 70 reflects the projection light emitted from the third lens group 92 and guides it to the projection surface SC, and reflects the light beam from the region including the projection surface SC to guide it to the third lens group 92. is there.
  • the reflective optical system 70 is disposed between the third lens group 92 and the projection surface SC, and has at least one curved mirror 70a.
  • the curved mirror 70a has a convex shape or a concave shape
  • the curved mirror 70a has a free curved surface shape or an aspherical shape.
  • the reflection optical system 70 may be flat.
  • the reflective optical system 70 has one convex curved mirror 70a.
  • the curved mirror 70a may be cut out in a region not used in the optical path.
  • the control circuit 80 can appropriately operate the image driving circuit 41, the image sensor 60, and the like based on a program incorporated therein or an instruction from an operation unit (not shown).
  • the control circuit 80 outputs a drive signal or an image signal to the image drive circuit 41 based on, for example, a video signal or other signal input from the outside, and causes the reflective liquid crystal element 40 to perform a display operation.
  • the control circuit 80 is communicably connected to the imaging device 60 via the interface 81, and can operate the imaging driving circuit 61 to cause the imaging device 60 to perform an imaging operation, as well as control signals and images. Data can be exchanged.
  • the control circuit 80 receives an image signal from the image sensor 60 via the interface 81 after the image pickup by the image sensor 60.
  • This image signal includes not only the projected image but also an additional image such as a handwritten character or a light emitting pen locus.
  • the control circuit 80 can not only optimize the state of the projection image from the received image signal, but also extract an additional image, and can superimpose and record the additional image on the projection image by the extraction. .
  • the optical path separating element 91 is disposed in a different position inside the projection optical system 10 and away from the optical path for guiding the illumination light to the reflective liquid crystal element 40, and the projection surface SC and its periphery (rectangular outer region). Is separated from the optical path of the projection optical system 10. Specifically, the optical path separation element 91 has an action of separating the projection optical path and the imaging optical path so as to be orthogonal to each other. As a result, the size of the optical path separation element 91 can be minimized, and the projection apparatus 100 can be advantageously reduced in size.
  • the optical path separation element 91 may be a prism or a mirror.
  • a polarization beam splitter or polarization mirror using polarization separation is desirable, but not limited to this, the light transmittance is simply controlled. It may be a half mirror.
  • the optical path separating element 91 is in the projection optical system 10. For this reason, when the optical path separating element 91 becomes large, it is necessary to increase the lens interval accordingly, and there is a risk of deteriorating optical performance. Therefore, it is desirable to make the optical path separation element 91 as small as possible.
  • the third lens group 92 is disposed between the optical path separation element 91 and the reflection optical system 70, and is commonly used for projection and imaging.
  • the third lens group 92 has a positive refractive power. Since the third lens group 92 commonly used for projection and imaging has a positive refractive power, the reflection optical system 70 can be made small, and the projection optical system 10 and thus the projection apparatus 100 can be reduced in size. .
  • the third lens group 92 includes, in order from the reflective liquid crystal element 40 side, a seventh lens L7, an eighth lens L8, a ninth lens L9, a tenth lens L10, and an eleventh lens L11. And have.
  • the third lens group 92 includes at least one aspheric lens.
  • a lens far from the reflective liquid crystal element 40 for example, the tenth and eleventh lenses L10 and L11 may be cut out in a region not used in the optical path as shown.
  • each of the first to third lens groups 11, 51, 92 includes at least one aspherical lens as described above.
  • the reflection optical system 70 and the third lens group 92 are commonly used for projection and imaging, the angle of view of the imaging optical system 50 is different from the angle of view of the projection optical system 10, and therefore the first lens group. 11 and the second lens group 51 have different aberrations to be corrected.
  • an aspheric lens for each of the first to third lens groups 11, 51, and 92, it is possible to improve the peripheral resolution and reduce the peripheral distortion.
  • the first lens group 11 disposed between the reflective liquid crystal element 40 and the optical path separation element 91 and the second lens group 51 disposed between the imaging element 60 and the optical path separation element 91. Satisfies the following conditional expression. 1.0 ⁇ fTr / fIm ⁇ 1.3 (1) However, the value fTr is the focal length of the first lens group 11, and the value fIm is the focal length of the second lens group 51.
  • Conditional expression (1) indicates that the focal length of the first lens group 11 disposed between the reflective liquid crystal element 40 and the optical path separation element 91 and the first distance disposed between the imaging element 60 and the optical path separation element 91.
  • This is a conditional expression for appropriately setting the focal length of the two lens group 51.
  • the first lens group 11 and the second lens group 51 have different focal lengths, and a difference in the angle of view between the projection optical system 10 and the imaging optical system 50 occurs due to the difference in focal length. Yes. Since the value fTr / fIm exceeds the lower limit of the conditional expression (1), the imaging optical system 50 can be made wider than the projection optical system 10, so that it is outside the projection image on the projection plane SC plane. The written character can be imaged.
  • the imaging optical system 50 is not excessively wide-angled, and an increase in the number of lenses in the second lens group 51 can be suppressed. Further, since the imaging optical system 50 does not become an excessively wide angle, it is possible to suppress a decrease in the resolution of the peripheral portion and an increase in distortion.
  • the projection apparatus 100 satisfies the following conditional expression. 0.2 ⁇ PRz / TL ⁇ 0.7 (2)
  • the value PRz is the distance on the optical axis OA from the reflective liquid crystal element 40 (more specifically, the display surface DD) to the surface of the optical path separating element 91 on the reflective liquid crystal element 40 side
  • the value TL is reflective type. This is the distance on the optical axis OA from the liquid crystal element 40 to the surface of the third lens group 92 closest to the projection surface SC (the eleventh lens L11 in FIG. 1) on the projection surface SC side.
  • Conditional expression (2) is a conditional expression for appropriately setting the position of the optical path separation element 91.
  • the optical path separation element 91 is not too close to the reflective liquid crystal element 40 side, and the influence of stray light due to strong light from the illumination optical system 20 is kept small. be able to. Further, since the installation space for the first lens group 11 and the second lens group 51 is increased, it is possible to configure the projection optical system 10 and the imaging optical system 50 in which aberrations are favorably corrected.
  • the optical path separating element 91 is not disposed too close to the projection surface SC, and the first lens group 11 and the second lens group 51 are simplified. Thus, the size of the projection optical system 10 and thus the projection apparatus 100 can be reduced.
  • the lens arranged in the projection optical system 10 closer to the projection plane SC than the optical path separation element 91 is commonly used for projection and imaging. It is. Therefore, if the optical path separation element 91 is too close to the projection surface SC, the number of lens groups that can be used in common is reduced, and the total optical length of the first lens group 11 and the second lens group 51 is increased. Since the first lens group 11 and the second lens group 51 are arranged in different directions, when the optical total length of the first lens group 11 and the second lens group 51 is increased, the projection apparatus is increased accordingly. . Accordingly, the projection optical system 10 and thus the projection apparatus 100 are reduced in size by falling below the upper limit of the conditional expression (2).
  • FIG. 2 shows the light path of the projection optical system 10 in the projection apparatus 100, and the light path of the imaging optical system 50 is not shown.
  • the projection light PL from the projection device 100 is projected onto the projection area SC1 (see FIG. 7A) in the projection plane SC.
  • the reflected light from the projection surface SC is incident on the projection device 100.
  • the reflected light incident on the projection device 100 is light reflected in the imaging region SC2 (see FIG. 7A) having a larger area than the projection region SC1.
  • the projection apparatus 100 is assumed to be a projector having an interactive function, and one of interactive functions is image recognition of handwritten characters.
  • the area to be imaged in the projection plane SC is wide including the area projected by the projection optical system 10 in the projection plane SC, so it is out of the projected range. Can also be taken.
  • the optical path separation element 91 for separating the optical path is disposed inside the projection optical system 10, and the optical path separation element 91 is disposed between the reflective liquid crystal element 40 and the imaging element 60. Since a part of the projection optical system 10 (the third lens group 92 and the reflection optical system 70 disposed on the projection surface SC side from the optical path separation element 91) can be used in common for projection and imaging, the projection optical system The number of parts can be reduced as compared with the case where the image pickup optical system is mounted separately from 10, and as a result, the projector 100 can be downsized. In addition, it is possible to obtain the imaging optical system 50 that has a peripheral resolving power equivalent to that of the projection optical system 10 and has little distortion.
  • the optical path separating element 91 is disposed at a position very close to the reflective liquid crystal element 40, strong light from the illumination optical system 20 for illuminating the reflective liquid crystal element 40 enters the imaging element 60. The risk of becoming higher.
  • the polarizing beam splitter 30 serving as the optical path of illumination light is disposed immediately before the reflective liquid crystal element 40, the first lens group 11 is disposed between the polarizing beam splitter 30 and the optical path separating element 91, and the optical path separating element.
  • the arrangement position of the optical path separation element 91 can be moved away from the polarization beam splitter 30 that is the optical path of the illumination light, and stray light caused by the illumination light Can be suppressed.
  • the first lens group 11 is disposed between the reflective liquid crystal element 40 and the optical path separation element 91
  • the second lens group 51 is disposed between the optical path separation element 91 and the imaging element 60, thereby capturing an image. It is not necessary to provide a re-imaging optical system that forms an image in the vicinity of the optical path separating element 91 after the light path separating element 91 is emitted on the optical path, so that the optical system can be simplified and miniaturized.
  • the first and second lens groups 11 and 51 having different refractive powers are arranged between the reflective liquid crystal element 40 and the optical path separating element 91 and between the optical path separating element 91 and the imaging element 60, respectively.
  • the angle wider than the projection angle of view it is possible to capture images up to the outer region of the projected image on the projection surface SC.
  • the size of the image sensor 60 can be made equal to or smaller than that of the reflective liquid crystal element 40, and the increase in size and cost of the optical system can be suppressed.
  • the surface described with “*” after each surface number is a surface having an aspherical shape, and the aspherical shape has the apex of the surface as the origin and the optical axis direction.
  • the Z axis (not necessarily coincident with the coordinates in FIG. 1) is taken, and the height in the direction perpendicular to the optical axis is h, and is expressed by the following “Expression 1”.
  • infinity is represented as “INF”
  • the display surface of the reflective liquid crystal element 40 is represented as “DD”
  • the aperture stop is represented as “ST”
  • the surface of the optical path separating element 91 is represented as “LD”
  • a curved mirror The reflecting surfaces 70a, 70b, and 70c are represented as “MR”
  • the projection surface is represented as “SC”
  • the imaging surface of the image sensor 60 is represented as “IS”.
  • Ai i-order aspheric coefficient
  • R radius of curvature
  • K conic constant
  • the surface with “**” after each surface number is a surface having an aspherical shape, and the free-form surface shape is the same as the aspherical shape with the vertex of the surface as the origin, and light
  • the Z axis is taken as the axial direction, and the height in the direction perpendicular to the optical axis is h.
  • Cj x m y coefficient n R: radius of curvature
  • K conical constant or conic constant
  • Example 1 The basic specifications of the projection optical system and the imaging optical system of Example 1 are shown below.
  • F number projection optical system
  • F number imaging optical system
  • F4.0 Display surface size of image display element: 13.5 mm x 7.6 mm
  • Image pickup surface size of the image pickup device 13.5 mm ⁇ 7.6 mm
  • Table 1 below shows data such as lens surfaces of the projection optical system and the imaging optical system of Example 1.
  • the description of the optical path separation element, the third lens group, and the reflection optical system (Surf. N: 14 to SC) used in common with the projection optical system is omitted ( The same applies to Example 2).
  • Table 2 shows the aspheric coefficients of the aspheric surfaces included in the projection optical system and the imaging optical system of Example 1.
  • a power of 10 for example, 2.5 ⁇ 10 ⁇ 02
  • E for example, 2.5E-02
  • Table 3 shows the free-form surface coefficients of the curved mirror 70a commonly used in the projection optical system and the imaging optical system of Example 1.
  • “*” represents a product
  • “**” represents a power (the same applies to the following examples).
  • FIG. 3 is a sectional view of the projection optical system 10A of the first embodiment. Specifically, it is a sectional view from the reflective liquid crystal element 40 to the reflective optical system 70.
  • FIG. 4 is a cross-sectional view of the imaging optical system 50A of the first embodiment, specifically, a cross-sectional view from the imaging element 60 to the reflection optical system 70.
  • the projection optical system 10A of Example 1 includes a polarization beam splitter 30, a first lens group 11, an optical path separation element 91, a third lens group 92, and a reflection optical system 70.
  • the imaging optical system 50A includes a parallel plate F2, a second lens group 51, an optical path separation element 91, a third lens group 92, and a reflection optical system 70.
  • the first lens group 11 includes a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, and a fifth lens L5 in order from the reflective liquid crystal element 40 that is an image display element. And a sixth lens L6.
  • the third lens group 92 includes, in order from the reflective liquid crystal element 40 side, a seventh lens L7, an eighth lens L8, a ninth lens L9, a tenth lens L10, and an eleventh lens L11.
  • the second lens group 51 includes, in order from the image sensor 60 side, a twelfth lens L12, a thirteenth lens L13, a fourteenth lens L14, a fifteenth lens L15, a sixteenth lens L16, and a seventeenth lens L17.
  • the first, tenth, eleventh, and twelfth lenses L1, L10, L11, and L12 are aspherical lenses.
  • the reflective optical system 70 has a refractive power, and is a convex free-form curved mirror 70a on the side close to the optical axis OA of the projection optical system 10A.
  • Reference numeral F ⁇ b> 1 indicates a parallel plate corresponding to the polarizing beam splitter 30 in which the image display element is disposed in front of the reflective liquid crystal element 40.
  • the parallel plate F1 may not be necessary. However, since the parallel plate F1 does not have refractive power, the optical system after the parallel plate F1 is not changed and the parallel plate F1 is excluded. You can also. In that case, the air space between the image display element and the first lens L1 may be set to an optimum position.
  • Reference numeral F2 is a parallel plate that is assumed to include, for example, an optical low-pass filter, an IR cut filter, a seal glass of the image sensor 60, and the like.
  • the imaging optical system 50 is arranged at a position bent in the orthogonal direction by the optical path separation element 91, but conversely, the projection optical system 10 is in a position bent in the orthogonal direction by the optical path separation element 91. You may arrange.
  • 5A and 5B are MTF (Modulation Transfer Function) characteristic diagrams on the projection surface SC of the projection optical system 10A.
  • 5A is an MTF characteristic diagram of the evaluation positions FP1 to FP3 in the projection region SC1 shown in FIG. 7A
  • FIG. 5B is an MTF characteristic diagram of the evaluation positions FP4 to FP6 in the projection region SC1 shown in FIG. 7A
  • 6A and 6B are MTF characteristics diagrams on the imaging surface IS of the imaging element 60 of the imaging optical system 50A.
  • 6A is an MTF characteristic diagram of the evaluation positions FP1 to FP3 in the imaging region SC2 shown in FIG. 7B
  • FIG. 6B is an MTF characteristic diagram of the evaluation positions FP4 to FP6 in the imaging region SC2 shown in FIG.
  • the projection area SC1 is a range in which a projection image is actually shown, and the area of the imaging area SC2 on the projection surface SC is larger than the area of the projection area SC1.
  • the vertical resolution of The wavelength weights for calculating the MTF are as follows (the same applies to the second embodiment). [Wavelength weight] Wavelength weight 656.3nm 34 587.6nm 63 546.1nm 100 486.1nm 83 435.8nm 26 404.7nm 8
  • Example 2 The basic specifications of the projection optical system and the imaging optical system of Example 2 are shown below.
  • Table 4 below shows data such as lens surfaces of the projection optical system and the imaging optical system of Example 2.
  • ⁇ Projection optics> Surf.N R [mm] D [mm] Nd ⁇ d DD 1.400 1 INF 13.660 1.5187 64.0 2 INF 1.000 3 40.496 15.914 1.8550 23.5 4 -98.169 8.972 5 81.768 3.227 1.4891 70.0 6 -42.587 2.980 1.8550 23.5 7 23.843 1.542 8 18.467 4.833 1.4891 70.0 9 -25.110 3.612 1.8550 23.5 10 -78.485 1.646 11 * 32.427 4.310 1.6347 23.9 12 * -84.647 1.846 13 ST INF 17.207 14 LD INF 25.000 1.8550 23.5 15 LD INF 1.000 16 118.247 4.534 1.8550 23.5 17 264.439 1.000 18 30.572 10.216 1.4891 70.0 19 -55.018 3.100 20 * -25.858 3.000 1.5305 56.0 21 * 96
  • Table 5 below shows the aspheric coefficients of the aspheric surfaces included in the projection optical system and the imaging optical system of Example 2.
  • FIG. 8 is a sectional view of the projection optical system 10B of the second embodiment. Specifically, it is a sectional view from the reflective liquid crystal element 40 to the reflective optical system 70.
  • FIG. 9 is a cross-sectional view of the image pickup optical system 50B of the second embodiment, specifically, a cross-sectional view from the image pickup element 60 to the reflection optical system 70.
  • the projection optical system 10B of Example 2 includes a polarization beam splitter 30, a first lens group 11, an optical path separation element 91, a third lens group 92, and a reflection optical system 70.
  • the imaging optical system 50 ⁇ / b> B includes a parallel plate F ⁇ b> 2, a second lens group 51, an optical path separation element 91, a third lens group 92, and a reflection optical system 70.
  • the first lens group 11 includes a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, and a fifth lens L5 in order from the reflective liquid crystal element 40 that is an image display element. And a sixth lens L6.
  • the third lens group 92 includes, in order from the reflective liquid crystal element 40 side, a seventh lens L7, an eighth lens L8, and a ninth lens L9.
  • the second lens group 51 includes, in order from the image sensor 60 side, a tenth lens L10, an eleventh lens L11, a twelfth lens L12, a thirteenth lens L13, a fourteenth lens L14, and a fifteenth lens L15.
  • the sixth, ninth, and fifteenth lenses L6, L9, and L15 are aspheric lenses.
  • the reflective optical system 70 includes an aspheric type curved mirror 70b having refractive power and an aspheric type curved mirror 70c.
  • 10A and 10B are MTF characteristics diagrams on the projection plane SC of the projection optical system 10B.
  • 11A and 11B are MTF characteristics diagrams on the imaging surface IS of the imaging element 60 of the imaging optical system 50B.
  • the number of lenses in the first and second lens groups 11 and 51 is the same, but it may be different. Further, the number of lenses constituting the first to third lens groups 11, 51, 92 may be one or more. Further, the radius of curvature and the core thickness of the constituting lens can be appropriately changed. Further, the reflection optical system 70 may not be used.
  • the image display element is not limited to the reflective liquid crystal element 40 such as LCOS, but a micromirror device including a micromirror, a transmissive LCD, or the like can be used.
  • the polarization beam splitter 30 is changed to an optical system suitable for each.
  • the light source of the illumination optical system 20 is not limited to the LED, and a mercury lamp, a laser, or the like can be used, and these light sources can be used in the same type or different types.
  • the number of red, green, and blue light sources may be arbitrarily combined according to the output. Further, it is possible to increase the brightness by adding an optical system for multiplexing and arranging a plurality of light sources for white or a specific color.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Engineering & Computer Science (AREA)
  • Multimedia (AREA)
  • Signal Processing (AREA)
  • Lenses (AREA)

Abstract

L'invention concerne un dispositif de projection 100 qui comprend un système optique de projection 10 qui grossit une image acquise à partir d'un élément à cristaux liquides réfléchissant 40 qui est un élément d'affichage d'image irradié par une lumière d'éclairage, et projette l'image sur un écran de projection SC. Un élément de séparation de trajet de lumière 91 est conçu pour séparer un trajet de lumière et dirige une partie du trajet de lumière vers une position différente de la position de la trajectoire de lumière pour la lumière d'éclairage à l'intérieur du système optique de projection 10. Un élément d'imagerie 60 est disposé dans le trajet de lumière séparé par l'élément de séparation de trajet de lumière 91, et une partie d'un faisceau provenant de l'écran de projection SC est séparée dans une direction différente du trajet de lumière pour le système optique de projection 10. Des premier et second groupes de lentilles 11, 51 ayant des puissances de réfraction mutuellement différentes sont disposés entre l'élément de séparation de trajet de lumière 91 et l'élément à cristaux liquides réfléchissant 40, et entre l'élément de séparation de trajet de lumière 91 et l'élément d'imagerie 60, respectivement. L'angle de vue d'imagerie est plus large que l'angle de vue de projection.
PCT/JP2016/071624 2015-07-23 2016-07-22 Dispositif de projection WO2017014317A1 (fr)

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109557645A (zh) * 2017-09-25 2019-04-02 佳能株式会社 光学系统和图像投影装置
CN111971605A (zh) * 2018-04-09 2020-11-20 索尼公司 光学系统和投影仪
US10897602B2 (en) 2018-07-27 2021-01-19 Fujifilm Corporation Projection display device for performing projection and imaging comprising optical image emitting light valve and imaging optical system
US11067876B2 (en) 2019-02-28 2021-07-20 Fujifilm Corporation Projection display device
JP2021121842A (ja) * 2020-01-31 2021-08-26 リコーインダストリアルソリューションズ株式会社 結像光学系および画像表示装置および撮像装置

Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH08339259A (ja) * 1995-06-13 1996-12-24 Sharp Corp 投影表示装置
JPH09305312A (ja) * 1996-05-15 1997-11-28 Sharp Corp 投影表示装置
JPH11355696A (ja) * 1998-06-05 1999-12-24 Nec Corp 画像表示装置及びプログラムを記録した記録媒体
JP2003044839A (ja) * 2001-07-26 2003-02-14 Nitto Kogaku Kk 画像入出力装置
JP2005266103A (ja) * 2004-03-17 2005-09-29 Canon Inc ズームレンズ及びそれを有する画像投射装置
JP2009205442A (ja) * 2008-02-28 2009-09-10 Panasonic Corp 画像投影装置
JP2010190939A (ja) * 2009-02-16 2010-09-02 Seiko Epson Corp 投射用ズームレンズ及び投射型画像表示装置
JP2010538685A (ja) * 2007-07-17 2010-12-16 エクスプレイ・リミテッド 光学投影方法及びシステム
JP2012189834A (ja) * 2011-03-11 2012-10-04 Canon Inc 投射型表示装置
JP2013073199A (ja) * 2011-09-29 2013-04-22 Casio Comput Co Ltd プロジェクタ装置
JP2013218262A (ja) * 2012-03-14 2013-10-24 Sharp Corp プロジェクタ

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH08339259A (ja) * 1995-06-13 1996-12-24 Sharp Corp 投影表示装置
JPH09305312A (ja) * 1996-05-15 1997-11-28 Sharp Corp 投影表示装置
JPH11355696A (ja) * 1998-06-05 1999-12-24 Nec Corp 画像表示装置及びプログラムを記録した記録媒体
JP2003044839A (ja) * 2001-07-26 2003-02-14 Nitto Kogaku Kk 画像入出力装置
JP2005266103A (ja) * 2004-03-17 2005-09-29 Canon Inc ズームレンズ及びそれを有する画像投射装置
JP2010538685A (ja) * 2007-07-17 2010-12-16 エクスプレイ・リミテッド 光学投影方法及びシステム
JP2009205442A (ja) * 2008-02-28 2009-09-10 Panasonic Corp 画像投影装置
JP2010190939A (ja) * 2009-02-16 2010-09-02 Seiko Epson Corp 投射用ズームレンズ及び投射型画像表示装置
JP2012189834A (ja) * 2011-03-11 2012-10-04 Canon Inc 投射型表示装置
JP2013073199A (ja) * 2011-09-29 2013-04-22 Casio Comput Co Ltd プロジェクタ装置
JP2013218262A (ja) * 2012-03-14 2013-10-24 Sharp Corp プロジェクタ

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109557645A (zh) * 2017-09-25 2019-04-02 佳能株式会社 光学系统和图像投影装置
JP2019060982A (ja) * 2017-09-25 2019-04-18 キヤノン株式会社 光学系、ズームレンズおよび画投影装置
US11029586B2 (en) 2017-09-25 2021-06-08 Canon Kabushiki Kaisha Optical system and image projection apparatus
CN109557645B (zh) * 2017-09-25 2021-12-31 佳能株式会社 光学系统和图像投影装置
CN111971605A (zh) * 2018-04-09 2020-11-20 索尼公司 光学系统和投影仪
EP3779553A4 (fr) * 2018-04-09 2021-05-19 Sony Corporation Système optique, et projecteur
CN111971605B (zh) * 2018-04-09 2023-09-12 索尼公司 光学系统和投影仪
US11835696B2 (en) 2018-04-09 2023-12-05 Sony Corporation Optical system and projector
US10897602B2 (en) 2018-07-27 2021-01-19 Fujifilm Corporation Projection display device for performing projection and imaging comprising optical image emitting light valve and imaging optical system
US11067876B2 (en) 2019-02-28 2021-07-20 Fujifilm Corporation Projection display device
JP2021121842A (ja) * 2020-01-31 2021-08-26 リコーインダストリアルソリューションズ株式会社 結像光学系および画像表示装置および撮像装置
JP7402702B2 (ja) 2020-01-31 2023-12-21 リコーインダストリアルソリューションズ株式会社 結像光学系および画像表示装置および撮像装置

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