WO2023281772A1 - 光学系、撮像装置、光学式接触センサ及び画像投影装置 - Google Patents

光学系、撮像装置、光学式接触センサ及び画像投影装置 Download PDF

Info

Publication number
WO2023281772A1
WO2023281772A1 PCT/JP2022/001072 JP2022001072W WO2023281772A1 WO 2023281772 A1 WO2023281772 A1 WO 2023281772A1 JP 2022001072 W JP2022001072 W JP 2022001072W WO 2023281772 A1 WO2023281772 A1 WO 2023281772A1
Authority
WO
WIPO (PCT)
Prior art keywords
point
rectangular area
optical system
optical axis
optical
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/JP2022/001072
Other languages
English (en)
French (fr)
Japanese (ja)
Inventor
卓也 今岡
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Panasonic Intellectual Property Management Co Ltd
Original Assignee
Panasonic Intellectual Property Management Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Panasonic Intellectual Property Management Co Ltd filed Critical Panasonic Intellectual Property Management Co Ltd
Priority to CN202280046163.6A priority Critical patent/CN117581144A/zh
Priority to JP2023533041A priority patent/JP7839969B2/ja
Priority to EP22837195.1A priority patent/EP4369073A4/en
Publication of WO2023281772A1 publication Critical patent/WO2023281772A1/ja
Priority to US18/545,433 priority patent/US12554188B2/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Images

Classifications

    • 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
    • G02B17/0856—Catadioptric systems comprising a refractive element with a reflective surface, the reflection taking place inside the element, e.g. Mangin mirrors
    • G02B17/086—Catadioptric systems comprising a refractive element with a reflective surface, the reflection taking place inside the element, e.g. Mangin mirrors wherein the system is made of a single block of optical material, e.g. solid catadioptric systems
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B13/00—Optical objectives specially designed for the purposes specified below
    • G02B13/001—Miniaturised objectives for electronic devices, e.g. portable telephones, webcams, PDAs, small digital cameras
    • G02B13/0055—Miniaturised objectives for electronic devices, e.g. portable telephones, webcams, PDAs, small digital cameras employing a special optical element
    • G02B13/0065—Miniaturised objectives for electronic devices, e.g. portable telephones, webcams, PDAs, small digital cameras employing a special optical element having a beam-folding prism or mirror
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B13/00—Optical objectives specially designed for the purposes specified below
    • G02B13/001—Miniaturised objectives for electronic devices, e.g. portable telephones, webcams, PDAs, small digital cameras
    • G02B13/0055—Miniaturised objectives for electronic devices, e.g. portable telephones, webcams, PDAs, small digital cameras employing a special optical element
    • G02B13/0065—Miniaturised objectives for electronic devices, e.g. portable telephones, webcams, PDAs, small digital cameras employing a special optical element having a beam-folding prism or mirror
    • G02B13/007—Miniaturised objectives for electronic devices, e.g. portable telephones, webcams, PDAs, small digital cameras employing a special optical element having a beam-folding prism or mirror the beam folding prism having at least one curved surface
    • 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
    • G02B17/0856—Catadioptric systems comprising a refractive element with a reflective surface, the reflection taking place inside the element, e.g. Mangin mirrors
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
    • G02B27/01—Head-up displays
    • G02B27/0101—Head-up displays characterised by optical features
    • 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
    • G03B17/02—Bodies
    • G03B17/17—Bodies with reflectors arranged in beam forming the photographic image, e.g. for reducing dimensions of camera
    • 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
    • G03B21/28—Reflectors in projection beam
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
    • G02B27/01—Head-up displays
    • G02B27/0101—Head-up displays characterised by optical features
    • G02B2027/0123—Head-up displays characterised by optical features comprising devices increasing the field of view

Definitions

  • the present disclosure relates to optical systems, imaging devices, optical contact sensors, and image projection devices.
  • Patent Document 1 discloses an optical system that enables single-focus, large-screen projection or imaging using a small prism.
  • the present disclosure provides a compact or low-profile optical system, an imaging device, an optical contact sensor, and an image projection device including the optical system.
  • An optical system is an optical system having a reduction-side reduction conjugate point and an expansion-side expansion conjugate point, comprising: a plurality of lenses; and a prism provided on the expansion side of the plurality of lenses. , provided.
  • the prism has a free-form curved first transmission surface, a first reflecting surface, a free-form second reflecting surface, and a free-form curved surface provided on the reduction side of the first transmitting surface. and a second transmission surface.
  • the first rectangular area at the reduction conjugate point has an imaging relationship that is conjugate with the second rectangular area at the enlargement conjugate point, and the optical axis is an axis passing through the centers of the most lenses among the plurality of lenses.
  • An optical system is an optical system having a reduction conjugate point on the reduction side and an expansion conjugate point on the expansion side, comprising: a plurality of lenses; a prism;
  • the first rectangular area at the reduction conjugate point has an imaging relationship that is conjugate with the second rectangular area at the enlargement conjugate point, and the optical axis is an axis passing through the centers of the most lenses among the plurality of lenses. do not cross
  • the prism has a first reflecting surface inclined at an angle larger than 40 degrees and smaller than 50 degrees with respect to a direction parallel to a first side having the shortest distance to the optical axis among four sides of the first rectangular area. and a second reflecting surface having positive power.
  • An optical system is an optical system having a reduction-side reduction conjugate point and an expansion-side expansion conjugate point.
  • a first rectangular region at the contraction conjugate point has an imaging relationship that is conjugate with a second rectangular region at the expansion conjugate point.
  • the optical system is configured to arrange the first rectangular area, the second surface, and the second rectangular area in this order or reverse order for a transparent body having a first surface including the second rectangular area and a second surface. Let the chief ray pass through the The second plane is not parallel to the first plane.
  • An imaging device includes the optical system according to the aspect described above and an imaging element that receives light passing through the optical system.
  • An optical contact sensor includes the imaging device according to the aspect described above and a light source that emits light toward the second rectangular area, and detects contact with the second rectangular area. .
  • An image projection device includes the optical system according to the aspect described above and an image forming element that projects an image onto a screen via the optical system.
  • FIG. 1 is a schematic perspective view showing the configuration of an optical system according to an embodiment.
  • FIG. 2 is a schematic perspective view for explaining the arrangement of the optical system according to the embodiment using a first plane that is a virtual plane.
  • FIG. 3 is a schematic perspective view for explaining the arrangement of the optical system according to the embodiment using a second plane that is a virtual plane.
  • FIG. 4 is a schematic perspective view for explaining the positional relationship between the reduction conjugate point and the expansion conjugate point of the optical system according to the embodiment.
  • FIG. 5 is a plan view showing the first rectangular area at the reduction conjugate point of the optical system according to the embodiment.
  • FIG. 6 is a perspective view showing an example of a prism included in the optical system according to the embodiment.
  • FIG. 7 is a six-sided view of the prism shown in FIG. 6.
  • FIG. 8 is a schematic perspective view showing light rays passing through the prism shown in FIG. 6;
  • FIG. 9 is a schematic perspective view showing the incident angle of light with respect to the first reflecting surface of the prism shown in FIG. 6.
  • FIG. 10 is a diagram showing intermediate imaging positions of the optical system according to the embodiment.
  • FIG. 11 is a schematic perspective view schematically showing an image on a main plane of the optical system according to the embodiment.
  • FIG. 12 is a schematic perspective view showing the maximum angle of a principal ray passing through the second rectangular region at the expansion conjugate point of the optical system according to the embodiment, and the angle at which the principal ray passes through the second surface of the transparent body; It is a diagram.
  • FIG. 12 is a schematic perspective view showing the maximum angle of a principal ray passing through the second rectangular region at the expansion conjugate point of the optical system according to the embodiment, and the angle at which the principal ray passes through the second surface
  • FIG. 13 is a schematic perspective view showing respective principal ray passing regions of the first surface and the second surface of the transparent body according to the embodiment.
  • FIG. 14 is a schematic cross-sectional view showing optical path lengths of principal rays in the transparent body according to the embodiment.
  • FIG. 15 is a schematic plan view showing a principal ray incident on a first point closest to the optical axis among four sides of the first rectangular area at the reduction conjugate point of the optical system according to the embodiment.
  • 16 is a schematic side view showing the angle at which the principal ray shown in FIG. 15 is incident on the second rectangular region at the enlarged conjugate point of the optical system according to the embodiment;
  • FIG. FIG. 17 is a schematic perspective view showing a modification of the transparent body.
  • FIG. 18 is a plan view showing principal rays passing through the optical system according to Example 1.
  • FIG. FIG. 19 is a side view showing principal rays passing through the optical system according to Example 5.
  • FIG. FIG. 20 is a diagram showing MTF characteristics of the optical system according to Example 1.
  • FIG. 21 is a diagram showing MTF characteristics of the optical system according to Example 2.
  • FIG. 22 is a diagram showing MTF characteristics of the optical system according to Example 3.
  • FIG. FIG. 23 is a diagram showing MTF characteristics of the optical system according to Example 4.
  • FIG. FIG. 24 is a diagram showing MTF characteristics of the optical system according to Example 5.
  • FIG. FIG. 25 is a block diagram showing an example of an imaging device provided with an optical system according to an embodiment;
  • FIG. 26 is a block diagram showing an example of an image projection device provided with the optical system according to the embodiment.
  • An optical system is an optical system having a reduction-side reduction conjugate point and an expansion-side expansion conjugate point, comprising: a plurality of lenses; and a prism provided on the expansion side of the plurality of lenses. , provided.
  • the prism has a free-form curved first transmission surface, a first reflecting surface, a free-form second reflecting surface, and a free-form curved surface provided on the reduction side of the first transmitting surface. and a second transmission surface.
  • the first rectangular area at the reduction conjugate point has an imaging relationship that is conjugate with the second rectangular area at the enlargement conjugate point, and the optical axis is an axis passing through the centers of the most lenses among the plurality of lenses.
  • the prism having a reflecting surface and a transmitting surface that are free-form surfaces is provided, it is possible to achieve both a wide angle and a compact optical system.
  • an optical system having a reduction conjugate point on the reduction side and an expansion conjugate point on the expansion side, comprising: a plurality of lenses; and a prism.
  • the first rectangular area at the reduction conjugate point has an imaging relationship that is conjugate with the second rectangular area at the enlargement conjugate point, and the optical axis is an axis passing through the centers of the most lenses among the plurality of lenses. do not cross
  • the prism has a first reflecting surface inclined at an angle larger than 40 degrees and smaller than 50 degrees with respect to a direction parallel to a first side having the shortest distance to the optical axis among four sides of the first rectangular area. and a second reflecting surface having positive power.
  • the prism further has a first transmission surface having a free-form surface shape, and a second transmission surface having a free-form surface shape provided on the reduction side of the first transmission surface.
  • the optical system may allow the principal ray to pass through the first transmitting surface, the first reflecting surface, the second reflecting surface, and the second transmitting surface in this order or reverse order.
  • the transmitting surface of the prism has a free-form surface shape, it is possible to achieve both a wide angle and a thin optical system. For example, a large second rectangular area can be secured.
  • An optical system is an optical system having a reduction conjugate point on the reduction side and an expansion conjugate point on the expansion side.
  • a first rectangular region at the contraction conjugate point has an imaging relationship that is conjugate with a second rectangular region at the expansion conjugate point.
  • the optical system is configured to arrange the first rectangular area, the second surface, and the second rectangular area in this order or reverse order for a transparent body having a first surface including the second rectangular area and a second surface. Let the chief ray pass through the The second plane may not be parallel to the first plane. Further, for example, the second surface may share one side with the first surface.
  • Reflection on the second surface can be reduced when the optical system is used in an imaging device. For example, it is possible to suppress the occurrence of ghost images.
  • the optical system since the optical system is not located on the back side of the first surface of the transparent body, it is possible to avoid applying a strong stress to the optical system when a contact force is applied to the first surface. be able to.
  • optical system according to one aspect of the present disclosure may satisfy the following condition (a).
  • ⁇ o maximum angle between the normal to the second rectangular area and the principal ray passing through the second rectangular area
  • ⁇ i when the principal ray passing through the second rectangular area at the maximum angle passes through the second surface is the angle between the principal ray and the normal to the second surface.
  • the optical system according to one aspect of the present disclosure includes a plurality of lenses, and the first rectangular region intersects an optical axis that is an axis passing through the centers of the most lenses among the plurality of lenses. It doesn't have to be.
  • the second rectangular area and the optical system can be prevented from overlapping when viewed from the normal direction of the second rectangular area. Therefore, since the optical system is not located on the back side of the first surface of the transparent body, it is possible to avoid applying stress to the optical system when a contact force is applied to the first surface. be able to.
  • an optical system includes the transparent body, and among four sides of the first rectangular region, a first side having the shortest distance to the optical axis, and the first side
  • a line segment connecting the centers of the side and the second side parallel to each other is set as the center line, the following condition (b) may be satisfied.
  • H1i Distance connecting two points on the second surface through which principal rays forming images on both ends of the first side Vi: on the second surface through which principal rays forming images on both ends of the center line pass
  • H1o Distance connecting two points on the first surface through which principal rays forming images at both ends of the first side
  • Vo Said distance through which principal rays forming images at both ends of the center line pass It is the distance connecting two points on the first surface.
  • an optical system includes the transparent body, and among four sides of the first rectangular region, a first side having the shortest distance to the optical axis, and the first side If the second side is parallel to the side, the following condition (c) may be satisfied.
  • H1i distance connecting two points on the second surface through which principal rays forming images on both ends of the first side pass
  • H2i on the second surface through which principal rays forming images on both ends of the second side pass
  • H1o Distance connecting two points on the first surface through which principal rays forming images on both ends of the first side pass
  • H2o Principal rays forming images on both ends of the second side It is the distance connecting two points on the first plane through which the line passes.
  • the optical system may include a prism provided on the enlargement side of the plurality of lenses.
  • the prism has a free-form curved first transmission surface, a first reflecting surface, a second reflecting surface having a positive power, and a free-form curved surface provided on the reduction side of the first transmitting surface. and a second transmission surface.
  • the optical system allows the principal ray to pass through the first transmitting surface, the first reflecting surface, the second reflecting surface, and the second transmitting surface in this order or in reverse order.
  • the prism has a free-form transmission surface and a reflection surface with positive power, it is possible to achieve both a wide angle and a thin optical system. For example, a large second rectangular area can be secured.
  • the first transmitting surface passes through a first point that is the closest point to the optical axis on the first side with the shortest distance to the optical axis among four sides of the first rectangular area.
  • a chief ray may diverge in a direction parallel to the optical axis and converge in a direction perpendicular to the optical axis.
  • the second transmission plane passes through a first point that is the closest point to the optical axis on the first side of the four sides of the first rectangular area that has the shortest distance to the optical axis.
  • a chief ray may be diverged in a direction parallel to the first side and converged in a direction perpendicular to the first side.
  • a direction parallel to the first side may be larger than a direction perpendicular to the first side.
  • the optical system according to one aspect of the present disclosure has an intermediate imaging position that is conjugate with each of the reduction conjugate point and the expansion conjugate point, and the intermediate imaging position is the second reflecting surface. and the second transmission surface.
  • the second point is the farthest point from the second rectangular area on the first side, and the second point is the closest point to the second rectangular area on the first side.
  • point is a fourth point, and the farthest point from the second rectangular area on the second side parallel to the first side of the four sides of the first rectangular area is the third point, and the point on the second side is the third point. If the point closest to the second rectangular area is the fifth point, the following condition (d) may be satisfied.
  • i1 incident angle when the principal ray passing through the second point is incident on the first reflecting surface
  • i2 incident angle when the principal ray passing through the third point is incident on the first reflecting surface
  • i3 incident angle when the principal ray passing through the fourth point is incident on the first reflecting surface
  • i4 The incident angle when the principal ray passing through the fifth point is incident on the first reflecting surface.
  • the incident angle of the chief ray passing through the fifth point may be larger than 65 degrees and smaller than 85 degrees when it is incident on the first reflecting surface.
  • the incident angle i4 is smaller than 85 degrees, the sensitivity to shape errors of the first reflecting surface can be suppressed, and the ease of manufacture can be enhanced.
  • the incident angle i4 is greater than 65 degrees, the size of the prism can be reduced.
  • the optical system may include a transparent body having a first surface including the second rectangular area and a second surface.
  • the optical system may pass a principal ray that passes through the first rectangular area, the second surface, and the second rectangular area in this order or reverse order.
  • the optical system when used in an imaging device, for example, it is possible to photograph an object that is in contact with the second surface of the transparent body. That is, the imaging device can be used as an optical contact sensor.
  • the transparent body may include a first medium having the first surface, and a plate-like second medium that is smaller than the first medium and has the second surface.
  • the second surface may be in contact with air, and the second medium may be adjacent to a surface opposite the second surface to a surface of the first medium that is different from the first surface.
  • optical system according to one aspect of the present disclosure may satisfy the following condition (e).
  • n1 refractive index of the first medium
  • n2 refractive index of the second medium
  • the refractive index n2 of the second medium may be greater than 1.45.
  • the refractive index n1 of the first medium may be greater than 1.3 and less than 1.5.
  • the loss due to reflection at the interface between the first medium and the second medium can be suppressed by making the refractive index n1 larger than 1.3.
  • a large angle of view can be ensured because the refractive index n1 is less than 1.5.
  • optical system according to one aspect of the present disclosure may satisfy the following condition (f).
  • the shape change of the first surface can be photographed because the shape of the light emitted from the second surface does not change.
  • the Young's modulus of the second medium may be greater than 400 MPa and less than 200000 MPa.
  • the shape change of the first surface can be photographed because the shape of light emitted from the second surface does not change.
  • the Young's modulus of the first medium may be greater than 0.01 MPa and less than 3 MPa.
  • the point closest to the optical axis on the first side having the shortest shortest distance to the optical axis among four sides of the first rectangular area is the first and the point closest to the optical axis on the second side parallel to the first side of the four sides of the first rectangular area is the sixth point, even if the following condition (g) is satisfied: good.
  • La optical path length in the transparent body of the principal ray passing through the first point
  • Lb optical path length in the transparent body of the principal ray passing through the sixth point.
  • the angle between the principal ray and the normal to the second surface may be less than 30 degrees.
  • an angle formed by a plane including the second surface and a plane including the first surface may be larger than 45 degrees and smaller than 85 degrees.
  • the maximum angle of the chief ray passing through the second rectangular area may be greater than 65 degrees.
  • the height of the optical system can be reduced while enlarging the second rectangular area.
  • optical system according to one aspect of the present disclosure may satisfy the following condition (h).
  • L1 the length of the first side with the shortest distance to the optical axis among the four sides of the first rectangular area
  • L2 the third side orthogonal to the first side among the four sides of the first rectangular area is the length of
  • optical system according to one aspect of the present disclosure may satisfy the following condition (i).
  • d the shortest distance between the first side of the four sides of the first rectangular area that has the shortest distance to the optical axis and the optical axis
  • D the first side of the four sides of the first rectangular area It is the length of the third orthogonal side.
  • the point closest to the optical axis on the first side having the shortest shortest distance to the optical axis among four sides of the first rectangular area is the first If a seventh point is a point that is included in the second rectangular area and has an imaging relationship with the first point, the following conditions (j1) and (j2) may be satisfied.
  • the size of the optical system can be reduced while ensuring a large second rectangular area.
  • X/d satisfies the condition (j1)
  • the condition (j2) for Y/d it is possible to achieve both miniaturization and widening of the angle of view of the optical system.
  • optical system according to one aspect of the present disclosure may satisfy the following condition (j3).
  • Z the distance between the first point and the seventh point along the direction parallel to the optical axis.
  • the point closest to the optical axis on the first side having the shortest shortest distance to the optical axis among four sides of the first rectangular area is the first If a seventh point is a point that is included in the second rectangular area and has an imaging relationship with the first point, the following condition (k) may be satisfied.
  • ⁇ i the width of the incident angle or the output angle formed by the principal ray passing through the first point in a plane that passes through the first side and is parallel to the first side and the optical axis
  • ⁇ o ⁇ i It is the width of the angle formed when the chief ray to be formed passes through the seventh point.
  • the size of the optical system can be reduced while enlarging the second rectangular area.
  • the lens closest to the first rectangular area may be D-cut on a side that does not include the optical axis in a direction perpendicular to the first side.
  • an angle between a plane including the second rectangular area and a plane including the first rectangular area may be larger than 85 degrees and smaller than 95 degrees.
  • an imaging device includes the optical system according to the aspect described above and an imaging element that receives light passing through the optical system.
  • an optical contact sensor includes the imaging device according to the aspect described above and a light source that emits light toward the second rectangular area, and detects contact with the second rectangular area. detect.
  • An image projection device includes the optical system according to the aspect described above and an image forming element that projects an image onto a screen via the optical system.
  • each figure is a schematic diagram and is not necessarily strictly illustrated. Therefore, for example, scales and the like do not necessarily match in each drawing. Moreover, in each figure, the same code
  • the x-axis, y-axis and z-axis indicate three axes of a three-dimensional orthogonal coordinate system.
  • the x-axis and the y-axis are parallel to two orthogonal sides of the first rectangular area.
  • the z-axis direction is the normal direction of the first rectangular area.
  • the x-axis direction is the height direction of the optical system. That is, in this specification, "reducing the height” means shortening the height in the x-axis direction. In this specification, the term “miniaturization” means shortening the length along at least one of the x-axis, y-axis, and z-axis.
  • a light ray passes through a surface means that a light ray is incident on the surface and reflected or transmitted. That is, "a ray of light passes through a reflecting surface” means that a ray of light is incident on the reflecting surface and is reflected by the reflecting surface. Reflection is specular in the microscopic plane. "A ray of light passes through a transmission surface” means that a ray of light enters a transmission surface and is transmitted through the transmission surface. During transmission, light rays are refracted according to the refractive index difference.
  • ordinal numbers such as “first” and “second” do not mean the number or order of constituent elements unless otherwise specified, so as to avoid confusion between constituent elements of the same kind and to distinguish between them. It is used for the purpose of
  • FIG. 1 is a schematic perspective view showing the configuration of an optical system 1 according to this embodiment.
  • the optical system 1 shown in FIG. 1 has a reduction conjugate point on the reduction side and an expansion conjugate point on the expansion side.
  • a reduction conjugate point is an imaging position on the reduction side of the optical system 1 and is defined as a first rectangular area 10 .
  • the expansion conjugate point is the imaging position on the expansion side of the optical system 1 and is defined as the second rectangular area 20 .
  • the first rectangular area 10 has an imaging relationship that is conjugate with the second rectangular area 20 . Note that the second rectangular area 20 may not be a perfect rectangle due to distortion.
  • the first rectangular area 10 is the area where the imaging plane is located
  • the second rectangular area 20 is the area where the object plane is located.
  • the first rectangular area 10 is the image display area for forming the image of the projection source
  • the second rectangular area 20 is the area where the projection surface such as the screen is located. Become. The optical relationship between the first rectangular area 10 and the second rectangular area 20 will be described later in detail.
  • the optical system 1 guides the light emitted from the second rectangular area 20 on the enlargement side to the first rectangular area 10 on the reduction side.
  • the traveling direction of light is reversed. Also, the relationship between the incident angle and the output angle (or the reflection angle) with respect to the predetermined surface is reversed.
  • the optical system 1 includes a plurality of lenses 30, a prism 40, and a transparent body 50.
  • a plurality of lenses 30, prisms 40, and transparent bodies 50 are arranged in this order from the reduction side of the optical system 1 to the enlargement side.
  • Each of the plurality of lenses 30 has a predetermined lens curved surface on at least one of the reduction side and the enlargement side.
  • each lens 30 is a bi-convex lens, a plano-convex lens, a convex meniscus lens, a bi-concave lens, a plano-concave lens, or a concave meniscus lens.
  • the lens curved surface may be an aspherical lens having a free curved surface.
  • the plurality of lenses 30 include rotationally symmetrical shaped lenses.
  • the optical system 1 includes an aperture stop.
  • the aperture stop is an optical member that is arranged between the plurality of lenses 30 and defines the range in which the light beam passes through the optical system 1 .
  • the ray that passes through the center of the aperture stop is the chief ray.
  • the prism 40 is provided on the enlargement side of the plurality of lenses 30 .
  • the prism 40 has a first transmission surface 41 , a first reflection surface 42 , a second reflection surface 43 and a second transmission surface 44 .
  • each of the first transmitting surface 41, the second reflecting surface 43 and the second transmitting surface 44 has a free curved shape.
  • the first reflecting surface 42 is a flat surface.
  • the prism 40 is formed using a transparent medium such as glass or resin.
  • the first transmitting surface 41 , the first reflecting surface 42 , the second reflecting surface 43 and the second transmitting surface 44 are each part of the outer surface of the prism 40 .
  • a specific configuration example of the prism 40 will be described later.
  • the transparent body 50 has a first surface 51 including the second rectangular area 20 and a second surface 52 .
  • the second surface 52 is a surface through which the principal ray passing through the first surface 51 passes.
  • Each of the first surface 51 and the second surface 52 is a plane.
  • second surface 52 is not parallel to first surface 51 .
  • the second surface 52 shares one side with the first surface 51 .
  • the second surface 52 is inclined at a predetermined angle with respect to the first surface 51 .
  • the transparent body 50 is formed using a transparent medium such as glass or resin. Note that the optical system 1 may not include the transparent body 50 .
  • FIG. 1 shows an optical axis 60 and a reference axis 61 perpendicular to the optical axis 60 .
  • Each of the optical axis 60 and the reference axis 61 is a virtual straight line extending in one direction.
  • the optical axis 60 is an axis passing through the centers of the largest number of lenses 30 .
  • the reference axis 61 is an axis orthogonal to the optical axis 60 and orthogonal to the first side 11 of the four sides of the first rectangular area 10 that has the shortest distance to the optical axis 60 .
  • each component of the optical system 1 is determined based on a virtual plane passing through the optical axis 60 and/or the reference axis 61 .
  • the arrangement of the optical system 1 will be described below with reference to FIGS. 2 and 3.
  • FIG. 1
  • FIG. 2 is a schematic perspective view for explaining the arrangement of the optical system 1 according to this embodiment using a first plane 70 that is a virtual plane.
  • a first plane 70 shown in FIG. 2 is a virtual plane perpendicular to the first rectangular area 10 and passing through the optical axis 60 and parallel to the first side 11 of the first rectangular area 10 .
  • the first plane 70 is the xz plane.
  • the space in which the optical system 1 is arranged can be divided into a first space 71 and a second space 72 with a first plane 70 as a boundary.
  • the first space 71 is the space on the negative side of the y-axis
  • the second space 72 is the space on the positive side of the y-axis.
  • all principal rays passing through the first rectangular area 10 pass through the first rectangular area 10 , the first transmitting surface 41 and the first reflecting surface 42 in the first space 71 .
  • the first rectangular area 10 , the first transmitting surface 41 and the first reflecting surface 42 are arranged substantially entirely in the first space 71 .
  • all principal rays passing through the first rectangular area 10 pass through the second reflecting surface 43 and the second transmitting surface 44 in the second space 72 .
  • substantially the entire surfaces of the second reflecting surface 43 and the second transmitting surface 44 are arranged in the second space 72 .
  • the prism 40 is arranged across the first space 71 and the second space 72 .
  • a plurality of lenses 30 are similarly arranged across the first space 71 and the second space 72 .
  • the second rectangular area 20 of the transparent body 50 and at least part of the second surface 52 are arranged in the first space 71 .
  • the surface arranged in the first space 71 is shaded with dots.
  • the contours of the surfaces arranged in the second space 72 are indicated by dashed lines (excluding the contour of the second rectangular area 20).
  • FIG. 3 is a schematic perspective view for explaining the arrangement of the optical system 1 according to this embodiment using a second plane 80 that is a virtual plane.
  • a second plane 80 shown in FIG. 3 is a virtual plane that passes through the optical axis 60 and is perpendicular to the first plane 70 .
  • Second plane 80 includes optical axis 60 and reference axis 61 .
  • the second plane 80 is the yz plane.
  • the space in which the optical system 1 is arranged can be divided into a third space 81 and a fourth space 82 with a second plane 80 as a boundary.
  • the third space 81 is the space on the negative side of the x-axis
  • the fourth space 82 is the space on the positive side of the x-axis.
  • all principal rays passing through the first rectangular area 10 pass through the second rectangular area 20 and the first transmission surface 41 in the third space 81 .
  • the second rectangular area 20 and the first transmitting surface 41 are arranged substantially entirely in the third space 81 .
  • the first reflecting surface 42 , the second reflecting surface 43 and the second transmitting surface 44 are arranged only in the third space 81 , only in the fourth space 82 , or straddling the third space 81 and the fourth space 82 .
  • the plurality of lenses 30 and the first rectangular regions 10 are arranged across the third space 81 and the fourth space 82 .
  • At least part of the second surface 52 of the transparent body 50 is arranged in the third space 81 . Note that in FIG. 3, the surface arranged in the third space 81 is shaded with dots, and its contour is represented by a dashed line.
  • FIG. 4 is a schematic perspective view for explaining the positional relationship between the reduction conjugate point and the expansion conjugate point of the optical system 1 according to this embodiment.
  • the first rectangular area 10 at the reduced conjugate point does not intersect the optical axis 60 . That is, the first rectangular area 10 is located at a position shifted by a predetermined distance in one direction from the optical axis 60 .
  • the first rectangular area 10 and the second rectangular area 20 have an imaging relationship.
  • the aspect ratio of the first rectangular area 10 and the aspect ratio of the second rectangular area 20 are equal to each other.
  • the aspect ratio is the length ratio between the short side and the long side of each rectangular area.
  • the second rectangular area 20 on the enlargement side has a larger area than the first rectangular area 10 on the reduction side. It should be noted that the second rectangular area 20 may not be a perfect rectangle due to distortion.
  • the angle between the plane containing the second rectangular area 20 and the plane containing the first rectangular area 10 is greater than 85 degrees and less than 95 degrees.
  • the second rectangular area 20 and the first rectangular area 10 are perpendicular.
  • the plane formed by the first rectangular area 10 is defined as the xy plane.
  • the second rectangular area 20 is parallel to the yz plane.
  • FIG. 4 shows a seventh point 201 included in the second rectangular area 20, which has an imaging relationship with the first point 101 on the first side 11 of the first rectangular area 10.
  • FIG. 4 shows a seventh point 201 included in the second rectangular area 20, which has an imaging relationship with the first point 101 on the first side 11 of the first rectangular area 10.
  • FIG. 4 When the optical system 1 is used in an imaging device, the chief ray emitted from the seventh point 201 passes through the prism 40 and the plurality of lenses 30 and forms an image at the first point 101 .
  • FIG. An eighth point 202, a ninth point 203, a tenth point 204, an eleventh point 205 and a twelfth point 206 are shown.
  • the second point 102 and the eighth point 202 have an imaging relationship.
  • the third point 103 and the ninth point 203 have an imaging relationship.
  • a fourth point 104 and a tenth point 204 have an imaging relationship.
  • the fifth point 105 and the eleventh point 205 have an imaging relationship.
  • the sixth point 106 and the twelfth point 206 have an imaging relationship.
  • FIG. 5 is a plan view showing the first rectangular area 10 at the reduction conjugate point of the optical system 1 according to the embodiment.
  • the planar shape of the first rectangular area 10 is a rectangle elongated in the y-axis direction.
  • the first rectangular area 10 has a first side 11 , a second side 12 , a third side 13 and a fourth side 14 .
  • the first side 11 is the side with the shortest distance to the optical axis 60 among the four sides of the first rectangular area 10 .
  • a first point 101 shown in FIG. 5 is the closest point to the optical axis 60 on the first side 11 . That is, the first point 101 is the leg of the perpendicular to the optical axis 60 on the first side 11 .
  • the first point 101 is the midpoint of the first side 11 .
  • a straight line connecting the first point 101 and the optical axis 60 on the xy plane is the reference axis 61 .
  • the second side 12 is a side parallel to the first side 11.
  • a sixth point 106 shown in FIG. 5 is the closest point to the optical axis 60 on the second side 12 .
  • the sixth point 106 is the midpoint of the second side 12 .
  • a sixth point 106 is the intersection of the second side 12 and the reference axis 61 .
  • the third side 13 is the side farther from the second rectangular area 20 of the two sides orthogonal to the first side 11 and the second side 12 .
  • the fourth side 14 is the side closer to the second rectangular area 20 of the two sides orthogonal to the first side 11 and the second side 12 .
  • a second point 102 is the farthest point from the second rectangular area 20 on the first side 11 .
  • a second point 102 is an end point of the first side 11 and an intersection point of the first side 11 and the third side 13 .
  • a third point 103 is the farthest point from the second rectangular area 20 on the second side 12 .
  • a third point 103 is an end point of the second side 12 and an intersection point of the second side 12 and the third side 13 .
  • a fourth point 104 is the closest point to the second rectangular area 20 on the first side 11 .
  • Each of the fourth points 104 is an end point of the first side 11 and an intersection point of the first side 11 and the fourth side 14 .
  • a fifth point 105 is the closest point to the second rectangular area 20 on the second side 12 .
  • the fifth points 105 are end points of the second side 12 and intersection points of the second side 12 and the fourth side 14, respectively.
  • the aspect ratio of the first rectangular area 10 is, for example, the ratio between L2 and L1.
  • L2:L1 is, for example, 3:2, 4:3, 16:9, 256:135, etc., but is not particularly limited.
  • the shortest distance between the first point 101 and the optical axis 60 is defined as d.
  • d corresponds to the amount of decentering of the first rectangular area 10 from the optical axis 60 .
  • the shortest distance d is shorter than the length D of the long side of the first rectangular area 10 . It satisfies the following condition (i).
  • d/D When d/D is smaller than 0.3, it is possible to suppress the increase in size of the optical system 1 .
  • the optical system 1 When the optical system 1 is used in an imaging device, if d/D is too large, the output angle from the second rectangular area 20 becomes too large, which may reduce the amount of light.
  • d/D since d/D is smaller than 0.3, it is possible to suppress a decrease in the amount of light.
  • d/D is larger than 0.1, it is possible to avoid overlapping of the prism 40 and the second rectangular area 20 when viewed from the normal direction of the second rectangular area 20 .
  • the positional relationship between the first rectangular area 10 and the second rectangular area 20 can be expressed based on the positional relationship between the first point 101 and the seventh point 201 shown in FIG. Specifically, the optical system 1 according to this embodiment satisfies the following conditions (j1) and (j2).
  • X is the distance between the first point 101 and the seventh point 201 along the direction parallel to the first side 11 (that is, the x-axis direction).
  • Y is the distance between the first point 101 and the seventh point 201 along the direction perpendicular to each of the first side 11 and the optical axis 60 (that is, the y-axis direction).
  • d is the amount of decentering shown in FIG.
  • X/d When X/d is greater than 5, it is possible to suppress the decrease in the amount of light in the peripheral portion (for example, on the side of the rectangular area). Moreover, since X/d is smaller than 20, the height of the optical system 1 can be reduced. Also preferably, X/d may be less than fifteen.
  • Y/d is greater than 5, the angle of view can be easily widened. Moreover, since Y/d is smaller than 20, the size of the optical system 1 can be reduced. Also preferably, Y/d may be less than 15.
  • optical system 1 further satisfies the condition (j3).
  • Z is the distance between the first point 101 and the seventh point 201 along the direction parallel to the optical axis 60 (that is, the z-axis direction).
  • Z/d When Z/d is greater than 10, an increase in chromatic aberration of magnification can be suppressed. Also, since Z/d is smaller than 30, the size of the optical system 1 can be reduced. Also preferably, Z/d may be less than 25.
  • FIG. 6 is a perspective view showing an example of the prism 40 included in the optical system 1 according to this embodiment.
  • FIG. 7 is a six-sided view of the prism 40 shown in FIG. Specifically, (a) is a front view, (b) is a left side view, (c) is a right side view, (d) is a rear view, (e) is a top view, and (f) is a bottom view.
  • the case where the prism 40 is viewed along the optical axis 60 from the side of the first rectangular area 10 is regarded as the front.
  • the negative side of the z-axis is regarded as the front
  • the positive side of the x-axis is regarded as upward
  • the negative side of the x-axis is regarded as downward
  • the positive side of the y-axis is regarded as the right side
  • the negative side of the y-axis is regarded as the left side.
  • FIG. 8 is a schematic perspective view showing light rays passing through the prism 40 shown in FIG.
  • FIG. 9 is a schematic perspective view showing the incident angle of light with respect to the first reflecting surface 42 of the prism 40 shown in FIG.
  • the prism 40 has a first transmission surface 41, a first reflection surface 42, a second reflection surface 43 and a second transmission surface 44. Specifically, part of the outer surface of the prism 40 functions as a first transmission surface 41 , a first reflection surface 42 , a second reflection surface 43 and a second transmission surface 44 .
  • the optical system 1 includes a first transmission surface 41, a first reflection surface 42, a second reflection surface 43, and a second transmission surface 44 (FIG. 9). ) are passed in this order or in reverse order.
  • the principal ray passes through the first transmitting surface 41, the first reflecting surface 42, the second reflecting surface 43, and the second transmitting surface 44 in this order.
  • the optical system 1 is used in an image projection apparatus, the principal ray passes through the second transmitting surface 44, the second reflecting surface 43, the first reflecting surface 42, and the first transmitting surface 41 in this order.
  • the first transmission surface 41 faces the negative side of the x-axis, as shown in FIGS. 6 and 7 (b), (c) and (f).
  • the first transmitting surface 41 functions as a plane of incidence of principal rays with respect to the prism 40 when the optical system 1 is used in an imaging device.
  • the first transmission surface 41 functions as an exit surface for principal rays from the prism 40 when the optical system 1 is used in an image projection apparatus.
  • the first transmission surface 41 causes the principal ray passing through the first point 101 to diverge in a direction parallel to the optical axis 60 (that is, in the z-axis direction). Converge in the direction perpendicular to 60. As a result, it is possible to reduce the size of the prism 40 and reduce the height of the optical system 1 while suppressing distortion.
  • the first reflecting surface 42 faces the positive side of the x-axis and the positive side of the y-axis, as shown in FIGS. 6 and 7 (a), (b), (c) and (e). .
  • the first reflecting surface 42 totally reflects the principal ray due to the difference in refractive index between the prism 40 and air.
  • the first reflecting surface 42 reflects the light that has passed through the first transmitting surface 41 toward the second reflecting surface 43, as shown in FIG. Alternatively, the light reflected by the second reflecting surface 43 is reflected toward the first transmitting surface 41 .
  • the first reflecting surface 42 is flat.
  • the first reflecting surface 42 is inclined at an angle larger than 40 degrees and smaller than 50 degrees with respect to the direction parallel to the first side 11 of the first rectangular area 10 (that is, the x-axis direction).
  • the angle ⁇ shown in FIG. 7B is the inclination angle of the first reflecting surface 42 with respect to the x-axis.
  • the angle ⁇ is, for example, 45 degrees.
  • the angles at which the principal rays are incident on the first reflecting surface 42 are defined as i1, i2, i3, and i4.
  • the angle of incidence is the angle between the ray and the normal to the surface, for example the angle between the chief ray and the normal to the first reflective surface 42 .
  • the incident angle i1 is the angle at which the principal ray passing through the second point 102 and the eighth point 202 is incident on the first reflecting surface 42 .
  • the incident angle i2 is the angle at which the principal ray passing through the third point 103 and the ninth point 203 is incident on the first reflecting surface 42 .
  • the incident angle i3 is the angle at which the principal ray passing through the fourth point 104 and the tenth point 204 is incident on the first reflecting surface 42 .
  • the incident angle i4 is the angle at which the principal ray passing through the fifth point 105 and the eleventh point 205 is incident on the first reflecting surface 42 .
  • the first reflecting surface 42 satisfies the following condition (d).
  • the incident angle i1 of the chief ray passing through the second point 102 which is the farthest point from the second rectangular area 20 along each of the x-axis and the y-axis, is the smallest incident angle.
  • the incident angle i4 of the principal ray passing through the fifth point 105 which is the closest point along each of the x-axis and the y-axis to the second rectangular area 20 in the first rectangular area 10, is the largest incident angle. .
  • the height and size of the optical system 1 can be reduced.
  • the incident angle i4 is, for example, larger than 65 degrees and smaller than 85 degrees. Since the incident angle i4 is smaller than 85 degrees, it is possible to suppress the occurrence of aberration when the shape error of the first reflecting surface 42 occurs, and to improve the ease of manufacturing.
  • the incident angle i4 is greater than 65 degrees, the size of the prism 40 can be reduced.
  • the angle of incidence i4 may be greater than 70 degrees. Also, the incident angle i4 may be less than 82 degrees.
  • the second reflecting surface 43 faces the positive side of the z-axis, as shown in FIGS. 6 and 7 (b), (c), (d), (e) and (f).
  • the second reflecting surface 43 totally reflects the principal ray due to the difference in refractive index between the prism 40 and air.
  • the second reflecting surface 43 reflects the light reflected by the first reflecting surface 42 toward the second transmitting surface 44, as shown in FIG. Alternatively, the light passing through the second transmitting surface 44 is reflected toward the first reflecting surface 42 .
  • the second reflecting surface 43 has positive power. Specifically, the converging action of the second reflecting surface 43 on the chief ray passing through the first point 101 is such that the direction parallel to the first side 11 (that is, the x-axis direction) is perpendicular to the first side 11 . direction (specifically, the y-axis direction). As a result, the size of the prism 40 can be reduced, and the height of the optical system 1 can be reduced.
  • the second transmission surface 44 faces the negative side of the z-axis, as shown in FIGS. 6 and 7 (a), (e) and (f).
  • the second transmission surface 44 is provided on the reduction side of the first transmission surface 41 .
  • the second transmission surface 44 functions as an exit surface for principal rays from the prism 40 when the optical system 1 is used in an imaging device.
  • the second transmission surface 44 functions as a plane of incidence of the principal ray with respect to the prism 40 when the optical system 1 is used in an image projection apparatus.
  • the second transmission surface 44 causes the principal ray passing through the first point 101 to diverge in a direction parallel to the first side 11 (that is, in the x-axis direction). Converge in a direction perpendicular to one side 11 (specifically, in the y-axis direction). As a result, it is possible to reduce the size of the prism 40 and reduce the height of the optical system 1 while suppressing distortion.
  • the optical system 1 has an intermediate imaging position that is conjugate with each of the reduction conjugate point and the expansion conjugate point.
  • intermediate imaging position 90 is positioned between second reflecting surface 43 and second transmitting surface 44 .
  • FIG. 10 is a diagram showing an intermediate imaging position 90 of the optical system 1 according to this embodiment. Thereby, the working distance can be shortened.
  • FIG. 11 is a schematic perspective view schematically showing an image on the main planes of the optical system 1 according to this embodiment.
  • three arrows are represented by a solid line, a dashed line and a dotted line on each surface.
  • a solid arrow extending from the second point 102 toward the fourth point 104 along the first side 11 is illustrated.
  • a dashed arrow is shown extending from the third point 103 to the fifth point 105 along the second side 12 .
  • a dashed arrow is shown extending from the center of the dotted arrow toward the center of the solid arrow.
  • the arrows of the same line type schematically represent the same image.
  • a broken line (not shown) following the tip of the solid-line arrow from the second rectangular region 20 to the first rectangular region 10 corresponds to the schematic optical path of the principal ray.
  • the principal ray passes through the second rectangular area 20, the second surface 52 of the transparent body 50, the first transmitting surface 41, the first reflecting surface 42, the second reflecting surface 43, the second transmitting surface 44, a plurality of lens 30 and the first rectangular area 10 in this order or in reverse order.
  • each of the first transmission surface 41, the second reflection surface 43, and the second transmission surface 44 has a free-form surface shape. Examples of specific shapes of each surface will be illustrated later.
  • FIG. 12 shows the maximum angle ⁇ o of the principal ray passing through the second rectangular region 20 of the optical system 1 according to this embodiment, and the angle ⁇ i at which the principal ray passes through the second surface 52 of the transparent body 50.
  • FIG. 13 is a schematic perspective view showing respective principal ray passing regions of the first surface 51 and the second surface 52 of the transparent body 50 according to the present embodiment.
  • FIG. 14 is a schematic cross-sectional view showing the optical path length of the principal ray inside the transparent body 50 according to this embodiment.
  • the transparent body 50 has a first surface 51 including the second rectangular area 20 and a second surface 52 .
  • the transparent body 50 has, for example, a flat shape having a first surface 51 and a surface opposite to the first surface 51 as main surfaces.
  • the chief ray passing through the second rectangular area 20 passes through the second surface 52 . That is, the first transmission surface 41 of the prism 40 is arranged so as to face the second surface 52 . For example, when viewed from the normal direction of the second rectangular area 20 , the first transmission surface 41 is arranged so as not to overlap the second rectangular area 20 of the first surface 51 of the transparent body 50 .
  • the principal ray 91 with the maximum incident angle (or exit angle) with respect to the second rectangular area 20 is represented by a solid line.
  • the maximum angle ⁇ o in FIG. 12 is the maximum angle of the principal ray passing through the second rectangular region 20 , that is, the maximum angle of incidence (or exit angle) of the principal ray 91 with respect to the second rectangular region 20 .
  • the angle ⁇ i is the angle at which the principal ray 91 passes through the second surface 52 .
  • the angle ⁇ i is the angle of emergence of the principal ray 91 from the second rectangular region 20 with respect to the second surface 52, or the incidence of the principal ray 91 incident on the second rectangular region 20 with respect to the second surface 52. is a corner.
  • the optical system 1 according to this embodiment satisfies the following condition (a).
  • the maximum angle ⁇ o is, for example, greater than 65 degrees. This makes it possible to reduce the height of the optical system 1 while enlarging the second rectangular region 20 . Preferably, the maximum angle ⁇ o may be greater than 70 degrees.
  • angle ⁇ i is, for example, smaller than 30 degrees. Thereby, reflection on the second surface 52 can be suppressed. Preferably, angle ⁇ i may be less than 20 degrees.
  • the area 22 where the principal ray passing through the second rectangular area 20 passes through the second surface 52 is represented by hatching dots.
  • the shape of the region 22 is trapezoidal.
  • the lengths H1o, H2o and Vo associated with the second rectangular area 20 are represented by double arrows.
  • the lengths H1i, H2i and Vi associated with region 22 are represented by double arrows.
  • the length H1o is the distance connecting two points on the first surface 51 through which principal rays forming images on both ends of the first side 11 of the first rectangular area 10 respectively pass. Both ends of the first side 11 are the second point 102 and the fourth point 104, respectively, as shown in FIG.
  • the length H1o is the distance between the eighth point 202 and the tenth point 204 of the second rectangular area 20 corresponding to the second point 102 and the fourth point 104, respectively.
  • the length H2o is the distance connecting two points on the first surface 51 through which principal rays forming images on both ends of the second side 12 of the first rectangular area 10 respectively pass. Both ends of the second side 12 are the third point 103 and the fifth point 105, respectively, as shown in FIG.
  • the length H2o is the distance between the ninth point 203 and the eleventh point 205 of the second rectangular area 20 corresponding to the third point 103 and the fifth point 105, respectively.
  • the length Vo is such that the principal ray forming an image passes through both ends of the center line. It is the distance connecting two points on the first surface 51 .
  • the center of the first side 11 is the first point 101 and the center of the second side 12 is the sixth point 106 .
  • the length H1i is the distance connecting two points on the second surface 52 through which principal rays forming images on both ends of the first side 11 of the first rectangular area 10 respectively pass.
  • H2i is the distance connecting two points on the second surface 52 through which principal rays forming images on both ends of the second side 12 of the first rectangular area 10 respectively pass.
  • the length Vi is such that the chief rays forming images pass through both ends of the center line. It is the distance connecting two points on the second surface 52 .
  • the optical system 1 satisfies the following condition (b1).
  • a large second rectangular area 20 can be secured.
  • the optical system 1 is used in an imaging device, a sufficient amount of light can be extracted from the depths of the transparent body 50 .
  • optical system 1 may satisfy the following condition (b2).
  • the height of the transparent body 50 can be reduced.
  • the following condition (b3) or (b4) may be satisfied.
  • optical system 1 satisfies the following condition (c1).
  • a large second rectangular area 20 can be secured.
  • the optical system 1 is used in an imaging device, a sufficient amount of light can be extracted from the depths of the transparent body 50 .
  • optical system 1 may satisfy the following condition (c2).
  • the height of the transparent body 50 can be reduced.
  • the following condition (c3) or (c4) may be satisfied.
  • the optical path length of the principal ray 92 within the transparent body 50 is defined as La.
  • the optical path length within the transparent body 50 of the principal ray 93 is defined as Lb. In this case, the following condition (g) is satisfied.
  • the principal ray 92 has a different incident angle width or exit angle width between when it enters or exits the first point 101 and when it enters or exits the seventh point 201 .
  • An example in which the optical system 1 uses an imaging device will be described below with reference to FIGS. 15 and 16.
  • FIG. 15 and 16 An example in which the optical system 1 uses an imaging device will be described below with reference to FIGS. 15 and 16.
  • FIG. 15 is a schematic plan view showing the principal ray 92 incident on the first point 101 closest to the optical axis 60 among the four sides of the first rectangular area 10 at the reduction conjugate point of the optical system 1 according to the present embodiment. is.
  • the incident angle ⁇ i shown in FIG. 15 is the width of the incident angle formed by the chief ray 92 incident on the first point 101 in the plane that passes through the first side 11 and is parallel to the first side 11 and the optical axis 60. is.
  • a translucent flat plate cover member is arranged between the lens 30 and the first rectangular region 10, but this member does not have a lens function.
  • FIG. 16 is a schematic cross-sectional view showing angles when the principal ray 92 shown in FIG. 15 is incident on the second rectangular region 20 at the expansion conjugate point of the optical system 1 according to the present embodiment.
  • the angle ⁇ o shown in FIG. 16 is the angle formed when the principal ray 92 forming the incident angle ⁇ i exits from the seventh point 201 .
  • the optical system 1 satisfies the following condition (k).
  • the size of the optical system 1 can be reduced while enlarging the second rectangular area 20 .
  • the second surface 52 is inclined with respect to the first surface 51 as shown in FIG.
  • the tilt angle ⁇ is an angle larger than 45 degrees and smaller than 85 degrees. Since the second surface 52 is inclined, it is possible to suppress the emission angle of light from the second surface 52 when the optical system 1 is used in an imaging device.
  • the transparent body 50 is formed using, for example, a homogeneous transparent material, but is not limited to this.
  • Transparent body 50 may be formed using a plurality of different materials. A modified example of a transparent body that can be used in place of the transparent body 50 will be described below with reference to FIG.
  • FIG. 17 is a schematic perspective view showing a modification of the transparent body.
  • a transparent body 350 shown in FIG. 17 includes a first medium 351 having a first surface 51 and a planar second medium 352 having a second surface 52 .
  • the second surface 52 is in contact with air.
  • the first medium 351 is the main body of the transparent body 350, and has a flat shape having the first surface 51 and the surface opposite to the first surface 51 as main surfaces.
  • the first medium 351 is made of, for example, a resin material such as silicon or urethane.
  • the second medium 352 is in contact with the first medium 351. Specifically, the surface of the second medium 352 opposite to the second surface 52 is in contact with the first medium 351 .
  • the second medium 352 is, for example, cover glass, but is not limited thereto.
  • the second medium 352 may be a transparent resin plate.
  • the first medium 351 and the second medium 352 are each formed using a material that transmits visible light.
  • the first medium 351 and the second medium 352 have different refractive indices.
  • the refractive index of the first medium 351 is defined as n1
  • the refractive index of the second medium 352 is defined as n2.
  • the transparent body 350 satisfies the following condition (e).
  • the refractive index n2 is greater than 1.45. This makes it possible to suppress field curvature. Also, the refractive index n1 is greater than 1.3 and less than 1.5. Reflection loss at the interface between the first medium 351 and the second medium 352 can be suppressed by making the refractive index n1 larger than 1.3. Moreover, a large angle of view can be ensured because the refractive index n2 is smaller than 1.5.
  • the first medium 351 has flexibility. Specifically, the first medium 351 is formed using a material that is soft enough to be easily deformed by human hands. The second medium 352 is harder than the first medium 351 .
  • the Young's modulus of the first medium 351 is defined as E1
  • the Young's modulus of the second medium 352 is defined as E2.
  • the transparent body 350 satisfies the following condition (f).
  • Young's modulus E1 is greater than 0.01 MPa and less than 3 MPa. This makes it possible to easily change the shape of the first medium 351 .
  • the first medium 351 is deformed when touched by a human hand or when the first medium 351 touches another object.
  • the optical system 1 is used in an imaging device, the deformation of the first surface 51 and the second rectangular area 20 can be used to photograph the shape change.
  • Young's modulus E2 is greater than 400 MPa and less than 200000 MPa (200 GPa). Thereby, even when the first medium 351 is deformed, the shape change of the second medium 352 is suppressed.
  • the second surface 52 of the second medium 352 functions as an exit surface of light from the transparent body 350 when the optical system 1 is used in an imaging device. Since the shape of the output surface can be kept constant without changing, the shape change of the first surface 51 can be photographed.
  • the second surface 52 functions as a light incident surface with respect to the transparent body 350, so that the projected image can be stabilized.
  • FIG. 18 is a plan view showing principal rays passing through the optical system according to Example 1.
  • Example 1, Example 2, and Example 3 similar to the optical system 1 shown in FIG.
  • the second rectangular areas 20 are arranged at positions that do not overlap.
  • FIG. 19 is a side view showing principal rays passing through the optical system according to Example 5.
  • FIG. The optical system according to Example 5 is arranged at a position where the second rectangular area 20 and the first rectangular area 10 overlap with respect to the optical axis 60 when the second rectangular area 20 is viewed from the front. That is, the first rectangular region 10 to the second rectangular region 20 are arranged side by side along the direction in which the optical axis 60 extends.
  • the optical system according to the fourth embodiment is similar to that of the fifth embodiment.
  • the lens 31 closest to the first rectangular area 10 may be a D-cut lens.
  • the lens 31 may be D-cut on the side that does not include the optical axis 60 in the direction perpendicular to the first side 11 .
  • the lens 31 has a plane parallel to the yz plane on the x-axis positive side.
  • a translucent plate cover member is arranged between the lens 31 and the first rectangular region 10, but this member does not have a lens function. This cover member is the same as that shown in FIG.
  • the unit of length is "mm". All the units of the angle of view are "degrees”. Further, in each example, a surface number is attached to each of a plurality of surfaces that affect light rays. The surface numbers are assigned in ascending order from the enlarged side (second rectangular area 20) to the reduced side (first rectangular area 10).
  • the type of surface Y curvature radius (curvature radius in the y-axis direction), conic coefficient, surface spacing, nd (refractive index for d-line), vd (Abbe number for d-line), and eccentricity data represent.
  • the decentration data indicates the displacement amounts X, Y, and Z of the target surface with respect to the previous surface of the optical system, and the normal directions ⁇ , ⁇ , and ⁇ of the target surface with respect to the previous surface.
  • optical system is used in an imaging device. That is, in each table, "object” represents the object plane, that is, the second rectangular area 20.
  • FIG. “Image” represents the imaging plane, that is, the first rectangular area 10 .
  • the free-form surface shape is defined by the following equation using a local Cartesian coordinate system (x, y, z) with the vertex of the surface as the origin.
  • z is the amount of sag on the surface parallel to the z-axis.
  • r is the radial distance, ie the square root of (x 2 +y 2 ).
  • c is the curvature at the face vertex.
  • k is the conic coefficient.
  • C j is the coefficient of the monomial x m y n .
  • Example 1 Table 1 shows the data of the main surfaces of the optical system according to Example 1.
  • the aperture diameter is 0.55 mm.
  • Table 2 shows the minimum and maximum sizes of the image formed in the first rectangular area 10 .
  • the optical system according to Example 1 includes, as the plurality of lenses 30, a first lens, a second lens, a third lens, a fourth lens, and a fifth lens in this order from the enlargement side to the reduction side.
  • a diaphragm is arranged between the third lens and the fourth lens.
  • a cover glass is arranged between the fifth lens and the reduction conjugate point.
  • the shape of the first lens is biconcave.
  • the shape of the second lens is biconvex.
  • the shape of the third lens is biconvex.
  • the shape of the fourth lens is a negative meniscus shape convex toward the first rectangular area 10 .
  • the shape of the fifth lens is biconvex.
  • the surface 4 is the first transmission surface 41 .
  • the surface 6 is the first reflecting surface 42 .
  • the surface 10 is the second reflecting surface 43 .
  • the surface 13 is the second transmission surface 44 .
  • Surface 14 is the first surface of the first lens.
  • Surface 15 is the second surface of the first lens.
  • Surface 16 is the first surface of the second lens.
  • Surface 17 is the second surface of the second lens.
  • Surface 18 is the first surface of the third lens.
  • Surface 19 is the second surface of the third lens.
  • Surface 20 is the aperture.
  • Surface 21 is the first surface of the fourth lens.
  • Surface 22 is the second surface of the fourth lens.
  • Surface 23 is the first surface of the fifth lens.
  • Surface 24 is the second surface of the fifth lens.
  • Surface 25 is the first surface of the cover glass.
  • Surface 26 is the second surface of the coverglass.
  • the surface 1, surface 2, surface 3, surface 5, surface 7, surface 8, surface 9, surface 11 and surface 12 are virtual surfaces for setting eccentricity and/or spacing. Further, in each lens and cover glass, the first surface and the second surface are surfaces facing back to each other, one of which functions as a light entrance surface and the other functions as a light exit surface.
  • Example 2 Table 6 shows the data of the main surfaces of the optical system according to Example 2.
  • the aperture diameter is 0.6 mm.
  • Table 7 shows the minimum and maximum sizes of the image formed in the first rectangular area 10 .
  • the optical system according to Example 2 includes a first lens, a second lens, a third lens, a fourth lens, and a fifth lens in this order from the enlargement side to the reduction side as the plurality of lenses 30 .
  • a diaphragm is arranged between the third lens and the fourth lens.
  • the shape of the first lens is a negative meniscus shape convex toward the first rectangular area 10 .
  • the shape of the second lens is biconvex.
  • the shape of the third lens is biconvex.
  • the shape of the fourth lens is a biconcave shape.
  • the shape of the fifth lens is biconvex.
  • the surface 4 is the first transmission surface 41 .
  • the surface 6 is the first reflecting surface 42 .
  • the surface 10 is the second reflecting surface 43 .
  • the surface 13 is the second transmission surface 44 .
  • Surface 14 is the first surface of the first lens.
  • Surface 15 is the second surface of the first lens.
  • Surface 16 is the first surface of the second lens.
  • Surface 17 is the second surface of the second lens.
  • Surface 18 is the first surface of the third lens.
  • Surface 19 is the second surface of the third lens.
  • Surface 20 is the aperture.
  • Surface 21 is the first surface of the fourth lens.
  • Surface 22 is the second surface of the fourth lens.
  • Surface 23 is the first surface of the fifth lens.
  • Surface 24 is the second surface of the fifth lens.
  • Surface 1, surface 2, surface 3, surface 5, surface 7, surface 8, surface 9, surface 11, surface 12 and surface 25 are virtual surfaces for setting eccentricity and/or spacing.
  • Table 11 shows the data of the main surfaces of the optical system according to Example 3.
  • the aperture diameter is 0.6 mm.
  • Table 12 shows the minimum and maximum sizes of the image formed in the first rectangular area 10 .
  • the optical system according to Example 3 includes, as a plurality of lenses 30, a first lens, a second lens, a third lens, a fourth lens, and a fifth lens in this order from the enlargement side to the reduction side.
  • a diaphragm is arranged between the third lens and the fourth lens.
  • the shape of the first lens is a negative meniscus shape convex toward the first rectangular region 10 .
  • the shape of the second lens is biconvex.
  • the shape of the third lens is biconvex.
  • the shape of the fourth lens is a negative meniscus shape convex toward the first rectangular area 10 .
  • the shape of the fifth lens is biconvex.
  • the surface 4 is the first transmission surface 41 in Example 3.
  • the surface 6 is the first reflecting surface 42 .
  • the surface 10 is the second reflecting surface 43 .
  • the surface 13 is the second transmission surface 44 .
  • Surface 14 is the first surface of the first lens.
  • Surface 15 is the second surface of the first lens.
  • Surface 16 is the first surface of the second lens.
  • Surface 17 is the second surface of the second lens.
  • Surface 18 is the first surface of the third lens.
  • Surface 19 is the second surface of the third lens.
  • Surface 20 is the aperture.
  • Surface 21 is the first surface of the fourth lens.
  • Surface 22 is the second surface of the fourth lens.
  • Surface 23 is the first surface of the fifth lens.
  • Surface 24 is the second surface of the fifth lens.
  • Surface 1, surface 2, surface 3, surface 5, surface 7, surface 8, surface 9, surface 11, surface 12 and surface 25 are virtual surfaces for setting eccentricity and/or spacing.
  • Table 16 shows the data of the main surfaces of the optical system according to Example 4.
  • the aperture diameter is 0.65 mm.
  • Table 17 shows the minimum and maximum sizes of the image formed in the first rectangular area 10 .
  • the optical system according to Example 4 includes, as the plurality of lenses 30, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens in this order from the enlargement side to the reduction side. I'm in.
  • a diaphragm is arranged between the third lens and the fourth lens.
  • a reflecting mirror is arranged between the fourth lens and the fifth lens.
  • the shape of the first lens is biconcave.
  • the shape of the second lens is biconvex.
  • the shape of the third lens is biconvex.
  • the shape of the fourth lens is a negative meniscus shape convex toward the first rectangular area 10 .
  • the shape of the fifth lens is a negative meniscus shape convex toward the first rectangular area 10 .
  • the shape of the sixth lens is a positive meniscus shape convex toward the first rectangular area 10 .
  • the surface 4 is the first transmission surface 41 in Example 4.
  • the surface 6 is the first reflecting surface 42 .
  • the surface 10 is the second reflecting surface 43 .
  • the surface 13 is the second transmission surface 44 .
  • Surface 14 is the first surface of the first lens.
  • Surface 15 is the second surface of the first lens.
  • Surface 16 is the first surface of the second lens.
  • Surface 17 is the second surface of the second lens.
  • Surface 18 is the first surface of the third lens.
  • Surface 19 is the second surface of the third lens.
  • Surface 20 is the aperture.
  • Surface 21 is the first surface of the fourth lens.
  • Surface 22 is the second surface of the fourth lens.
  • Surface 27 is the first surface of the fifth lens.
  • Surface 28 is the second surface of the fifth lens.
  • Surface 29 is the first surface of the sixth lens.
  • Surface 30 is the second surface of the sixth lens.
  • surface 1, surface 2, surface 3, surface 5, surface 7, surface 8, surface 9, surface 11, surface 12, surface 23, surface 24, surface 25 and surface 26 set eccentricity and/or spacing. It is
  • Table 21 shows the data of the main surfaces of the optical system according to Example 5.
  • the aperture diameter is 1.04 mm.
  • Table 22 shows the minimum and maximum sizes of the image formed in the first rectangular area 10 .
  • a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens are arranged from the enlargement side to the reduction side. They are included in this order.
  • a diaphragm is arranged between the fourth lens and the fifth lens.
  • the shape of the first lens is biconcave.
  • the shape of the second lens is a positive meniscus shape convex toward the first rectangular area 10 .
  • the shape of the third lens is a positive meniscus shape convex toward the first rectangular area 10 .
  • the shape of the fourth lens is biconvex.
  • the shape of the fifth lens is a biconcave shape.
  • the shape of the sixth lens is biconvex.
  • the shape of the seventh lens is biconvex.
  • the surface 10 is the second reflecting surface 43 in Example 5.
  • the surface 13 is the second transmission surface 44 .
  • Surface 14 is the first surface of the first lens.
  • Surface 15 is the second surface of the first lens.
  • Surface 16 is the first surface of the second lens.
  • Surface 17 is the second surface of the second lens.
  • Surface 18 is the first surface of the third lens.
  • Surface 19 is the second surface of the third lens.
  • Surface 20 is the first surface of the fourth lens.
  • Surface 21 is the second surface of the fourth lens.
  • Surface 22 is the aperture.
  • Surface 23 is the first surface of the fifth lens.
  • Surface 24 is the second surface of the fifth lens.
  • Surface 25 is the first surface of the sixth lens.
  • Surface 26 is the second surface of the sixth lens.
  • Surface 27 is the first surface of the seventh lens.
  • Surface 28 is the second surface of the seventh lens.
  • Surface 1, surface 2, surface 3, surface 4, surface 5, surface 6, surface 7, surface 8, surface 9, surface 11, surface 12 and surface 29 are virtual surfaces for setting eccentricity and/or spacing.
  • surfaces 27 and 28 are aspherical surfaces. It should be noted that the surfaces 27 and 28 are respectively one entrance surface or exit surface of the plurality of lenses 30 .
  • Table 25 shows the shape data of surfaces 27 and 28 having aspherical shapes.
  • the shape of the aspherical surface is defined by the following formula.
  • z is the amount of sag on the surface parallel to the z-axis.
  • r is the radial distance, ie the square root of (x 2 +y 2 ).
  • c is the curvature at the face vertex.
  • k is the conic coefficient.
  • A, B, C and D are the 4th, 6th, 8th and 10th coefficients of r, respectively.
  • Table 26 shows various parameters of the optical systems according to Examples 1 to 5. Various parameters are parameters related to the conditions (a) to (k) described in the embodiment. Note that Young's moduli E1 and E2 related to condition (f) are omitted because they are not related to optical characteristics.
  • MTF Modulation Transfer Function
  • FIGS. 20 to 24 are diagrams showing the MTF (Modulation Transfer Function) characteristics of the optical systems according to Examples 1 to 5, respectively.
  • the horizontal axis represents the defocus amount (unit: mm), and the vertical axis represents the contrast ratio.
  • the dashed line graph in the figure represents the MTF characteristics in the x-axis direction.
  • a solid line graph represents the MTF characteristics in the y-axis direction.
  • the MTF characteristics were obtained at a spatial frequency of 60 lines/1 mm.
  • Each figure shows four types of graphs (f1, f2, f3, f4) for each image height in each of the x-axis direction and the y-axis direction.
  • the image height is represented by a position within the first rectangular area 10 . Specific values of x from f1 to f4 are as shown in Table 27.
  • f1 is the position closest to the optical axis 60 of the first rectangular area 10, that is, the first point 101.
  • the first rectangular area 10 is shown with an x coordinate range of -0.758 to +0.758 and a y coordinate range of 0 to -0.2688. Since there is a symmetrical relationship between the negative and positive directions of the x-axis, only cases where the x-coordinate is in the positive range are shown.
  • FIG. 25 is a block diagram showing an example of an imaging device 400 including the optical system 1 according to this embodiment.
  • An imaging device 400 shown in FIG. 25 photographs a subject 401 .
  • the imaging device 400 includes an optical system 1 , a control section 410 and an imaging element 420 .
  • the control unit 410 controls the entire imaging device 400 and each component such as the imaging element 420 .
  • the control unit 410 is, for example, a CPU (Central Processing Unit) or a microprocessor.
  • the control unit 410 includes one or more memories, input/output ports, and the like.
  • the control unit 410 includes a nonvolatile memory in which control programs and the like are recorded, and a volatile memory that is a program execution area.
  • the imaging element 420 is a CCD (Charge Coupled Device) image sensor, a CMOS (Complementary Metal Oxide Semiconductor) image sensor, or the like.
  • An imaging surface of the imaging element 420 is arranged in the first rectangular area 10 .
  • the imaging device 420 receives light incident on the first rectangular area 10 via the optical system 1 and converts it into an electrical image signal.
  • the optical system 1 is miniaturized, so the imaging device 400 can also be miniaturized.
  • the imaging device 400 is used as a contact sensor, a tactile sensor, a fingerprint sensor, a sensing camera, or the like that detects contact of the subject 401 with the transparent body 50 of the optical system 1 . By applying this, the imaging device 400 can also be applied to a robot hand.
  • the imaging device 400 can be used as a road surface sensor that detects road surface conditions.
  • imaging device 400 can be used in self-driving vehicles.
  • the optical system 1 of the imaging device 400 does not have to include the transparent body 50 .
  • FIG. 26 is a block diagram showing an example of an image projection device 500 including the optical system 1 according to this embodiment.
  • An image projection device 500 shown in FIG. 26 projects an image (or video) onto a screen 501 .
  • the image projection device 500 includes an optical system 1 , a control section 510 , a light source 520 and an image forming element 530 .
  • the control unit 510 controls the entire image projection device 500 and each component such as the light source 520 and the image forming element 530 .
  • Control unit 510 is, for example, a CPU or a microprocessor.
  • the control unit 510 includes one or more memories, input/output ports, and the like.
  • the control unit 510 includes a nonvolatile memory in which control programs and the like are recorded, and a volatile memory that is a program execution area.
  • the light source 520 includes a solid light emitting device such as an LED (Light Emitting Device) or a laser device.
  • the light source 520 includes, for example, phosphors, etc., and generates and outputs desired visible light (eg, RGB).
  • the image forming element 530 includes an optical member such as a liquid crystal or a DMD (Digital Mirror Device).
  • the image forming element 530 is a DLP (Digital Light Processing) substrate with a DMD.
  • Imaging element 530 utilizes visible light from light source 520 to generate an image (or video).
  • the image forming surface of the image forming element 530 is arranged in the first rectangular area 10 .
  • the image forming element 530 emits the light emitted from the first rectangular area 10 toward the screen 501 via the optical system 1 .
  • the optical system 1 is miniaturized, so the image projection device 500 can also be miniaturized.
  • the image projection device 500 is, for example, a projector, but is not limited to this.
  • the image projection device 500 may be a transparent display device that projects on a window glass as a display surface, a head-up display, or the like.
  • optical system imaging device, and image projection device according to one or more aspects have been described above based on the embodiments, the present disclosure is not limited to these embodiments. As long as they do not deviate from the gist of the present disclosure, various modifications that a person skilled in the art can think of are applied to the present embodiment, and forms constructed by combining the components of different embodiments are also included within the scope of the present disclosure. be
  • the first reflecting surface 42 does not have to be flat.
  • the first reflecting surface 42 may have a free-form surface shape.
  • each of the first rectangular region 10 and the second rectangular region 20 may be a square.
  • the first rectangular region 10 and the second rectangular region 20 may not be strictly rectangular, may have different lengths of two sides facing each other, and may not be parallel. In this case, the length difference is, for example, about several percent of the side length.
  • the angle formed by the two sides may be in the range of about ⁇ 5 degrees.
  • each side may not be straight, but may be curved. When the side is curved, the amount of deviation from the straight line connecting the two vertices is, for example, within several tens of percent of the distance between the two vertices.
  • the second rectangular region 20 may not be a perfect plane, and may have a concave or convex shape. If the second rectangular region 20 is not flat, the amount of deviation from the plane is, for example, within several percent of the length of a line segment (e.g., diagonal line or side) connecting two vertices of the second rectangular region 20.
  • the first transmission surface of the prism may not have a free-form surface shape.
  • the main surface of the optical system 1 in which of the first space 71 and the second space 72 the main surface of the optical system 1 is arranged may be appropriately adjusted by providing an additional reflecting surface or the like.
  • the third space 81 and the fourth space 82 the main surfaces of the optical system 1 are arranged may be appropriately adjusted, for example, by providing an additional reflecting surface.
  • the optical system 1 includes a transparent member having a first transmission surface 41, a reflection mirror having a first reflection surface 42, a reflection mirror having a second reflection surface 43, and a second transmission A transparent member having a surface 44 may be included. That is, each facet may be made up of separate optical components rather than made up of an integrated prism.
  • the present disclosure can be used as a compact or low-profile optical system, and can be used, for example, in imaging devices and image projection devices.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Lenses (AREA)
PCT/JP2022/001072 2021-07-09 2022-01-14 光学系、撮像装置、光学式接触センサ及び画像投影装置 Ceased WO2023281772A1 (ja)

Priority Applications (4)

Application Number Priority Date Filing Date Title
CN202280046163.6A CN117581144A (zh) 2021-07-09 2022-01-14 光学系统、摄像装置、光学式接触传感器及图像投影装置
JP2023533041A JP7839969B2 (ja) 2021-07-09 2022-01-14 光学系、撮像装置、光学式接触センサ及び画像投影装置
EP22837195.1A EP4369073A4 (en) 2021-07-09 2022-01-14 OPTICAL SYSTEM, IMAGING DEVICE, OPTICAL CONTACT SENSOR AND IMAGE PROJECTION DEVICE
US18/545,433 US12554188B2 (en) 2021-07-09 2023-12-19 Optical system, imaging device, optical contact sensor, and image-projecting device

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2021-114029 2021-07-09
JP2021114029 2021-07-09

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US18/545,433 Continuation US12554188B2 (en) 2021-07-09 2023-12-19 Optical system, imaging device, optical contact sensor, and image-projecting device

Publications (1)

Publication Number Publication Date
WO2023281772A1 true WO2023281772A1 (ja) 2023-01-12

Family

ID=84800613

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2022/001072 Ceased WO2023281772A1 (ja) 2021-07-09 2022-01-14 光学系、撮像装置、光学式接触センサ及び画像投影装置

Country Status (5)

Country Link
US (1) US12554188B2 (https=)
EP (1) EP4369073A4 (https=)
JP (1) JP7839969B2 (https=)
CN (1) CN117581144A (https=)
WO (1) WO2023281772A1 (https=)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TWI772185B (zh) * 2021-09-17 2022-07-21 大陽科技股份有限公司 成像鏡頭驅動模組與電子裝置

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20190243113A1 (en) * 2018-02-07 2019-08-08 Idemia Identity & Security France One-piece optical element with diaphragm
JP2020194115A (ja) 2019-05-29 2020-12-03 パナソニックＩｐマネジメント株式会社 光学系、画像投写装置および撮像装置
JP2021117315A (ja) * 2020-01-24 2021-08-10 セイコーエプソン株式会社 投写光学系、およびプロジェクター

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3727543B2 (ja) * 2000-05-10 2005-12-14 三菱電機株式会社 画像表示装置
US7448760B2 (en) * 2004-12-13 2008-11-11 Nittoh Kogaku K.K. Optical system and rear projector
NZ706893A (en) * 2010-12-24 2017-02-24 Magic Leap Inc An ergonomic head mounted display device and optical system
US9128365B2 (en) * 2011-04-01 2015-09-08 Seiko Epson Corporation Projector, projection unit, and interactive board
JP6141584B2 (ja) * 2012-01-24 2017-06-07 アリゾナ ボード オブ リージェンツ オン ビハーフ オブ ザ ユニバーシティ オブ アリゾナ 小型視線追従型ヘッドマウントディスプレイ
EP3654083B1 (en) 2017-07-10 2024-10-09 Sony Group Corporation Image display device and projection optical system
JP7459523B2 (ja) * 2020-01-23 2024-04-02 セイコーエプソン株式会社 投写光学系およびプロジェクター
WO2022107592A1 (ja) * 2020-11-20 2022-05-27 パナソニックＩｐマネジメント株式会社 光学系、画像投写装置および撮像装置

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20190243113A1 (en) * 2018-02-07 2019-08-08 Idemia Identity & Security France One-piece optical element with diaphragm
JP2020194115A (ja) 2019-05-29 2020-12-03 パナソニックＩｐマネジメント株式会社 光学系、画像投写装置および撮像装置
JP2021117315A (ja) * 2020-01-24 2021-08-10 セイコーエプソン株式会社 投写光学系、およびプロジェクター

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP4369073A4

Also Published As

Publication number Publication date
US20240126157A1 (en) 2024-04-18
JP7839969B2 (ja) 2026-04-03
EP4369073A1 (en) 2024-05-15
US12554188B2 (en) 2026-02-17
JPWO2023281772A1 (https=) 2023-01-12
CN117581144A (zh) 2024-02-20
EP4369073A4 (en) 2024-11-06

Similar Documents

Publication Publication Date Title
JP7847353B2 (ja) 光学系、画像投写装置および撮像装置
CN110888288B (zh) 投影光学系统及图像投影装置
TWI795061B (zh) 光學成像系統
CN104049339B (zh) 投影光学系统与投影仪设备
TWI521233B (zh) 光學成像鏡頭及應用此鏡頭之電子裝置
JP6035416B2 (ja) 投写型映像表示装置
JP2015143796A (ja) 広角レンズ
CN115668025A (zh) 折叠光学系统
CN113805311B (zh) 光学镜头、摄像模组及电子设备
JP6393906B2 (ja) 投写光学系および画像投写装置
JP2005301074A (ja) 投影光学系
CN108027498A (zh) 投射光学系统以及图像投射装置
CN116601539A (zh) 光学系统、图像投影装置以及摄像装置
JP4114515B2 (ja) 投映用ズームレンズ及びこれを備えたプロジェクター
WO2023281772A1 (ja) 光学系、撮像装置、光学式接触センサ及び画像投影装置
JP2004077825A (ja) 投写光学系およびこれを用いた投写型画像表示装置
CN214504006U (zh) 投影镜头、投影显示系统及投影显示装置
JP4478408B2 (ja) 結像光学系、撮像装置、画像読み取り装置および投射型画像表示装置
TWI809587B (zh) 投影鏡頭
CN111971605A (zh) 光学系统和投影仪
JP2004295042A (ja) 画像投影装置
TWI525340B (zh) 光學成像鏡頭及應用此鏡頭之電子裝置
JP2018045025A (ja) 撮像光学系、撮像装置及び投影撮像システム
JP2007017708A (ja) 撮像光学系、および撮像光学ユニット
JP4807362B2 (ja) 光学系の設計方法及び製造方法

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 22837195

Country of ref document: EP

Kind code of ref document: A1

WWE Wipo information: entry into national phase

Ref document number: 2023533041

Country of ref document: JP

WWE Wipo information: entry into national phase

Ref document number: 202280046163.6

Country of ref document: CN

WWE Wipo information: entry into national phase

Ref document number: 2022837195

Country of ref document: EP

NENP Non-entry into the national phase

Ref country code: DE

ENP Entry into the national phase

Ref document number: 2022837195

Country of ref document: EP

Effective date: 20240209