JP2016035544A - Projection unit and projector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a projection unit that can project a video projected by a projector 10 on a normal glass.SOLUTION: A projection unit 100 of the present invention is a projection unit 100 that is used by being attached to a projector 10 projecting videos and reflects a video projected by the projector 10 on a glass to display the video, and has a first principal surface 51 and a second principal surface 52 opposite to the first principal surface 51, where the first principal surface 51 has a micro lens array 57 comprising a plurality of unit micro lenses provided thereon. The projection unit 100 further comprises an intermediate image screen 50 in which the video projected by the projector is formed on the micro lens array, and projection optical systems (81 and 82) that project the intermediate image screen 50 on the glass.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a projection unit that is used by being attached to a projector that projects an image, displays the image projected by the projector by reflecting the image on glass, and a projector having the main configuration of the projection unit.

  Conventionally, in order to project an image projected by a projector, it has been necessary to project it onto a light diffusion surface such as a reflective layer. For example, in a head up display (HUD) device or the like, a reflective layer called a combiner is provided on glass or the like, and an image projected by a projector is projected on the combiner.

As such an apparatus, for example, in Patent Document 1 (Japanese Patent Laid-Open No. 4-56633), a virtual image display image is reflected in front of the front windshield by reflecting it with a semi-transparent combiner formed on the front windshield. A head-up display device including a projector for projecting is disclosed.
JP-A-4-56633

  The conventional projector has a problem that an image cannot be projected on general glass having a reflectance of 10% or less without using a reflective layer such as a combiner.

  If it becomes possible to project images on general glass, the need for such glass can be used for advertisements and public relations, etc., but there is a widespread need, but bright images are projected on general-purpose glass with low reflectivity. It was a problem that could not be done.

  The present invention is for solving the above-described problems, and the projection unit according to the present invention is used by being attached to a projector that projects an image, and reflects the image projected by the projector on glass. A projection unit for displaying a microlens array having a first main surface and a second main surface opposite to the first main surface, the microlens array comprising a plurality of unit microlenses on the first main surface. And an intermediate image screen on which an image projected by the projector is formed on the microlens array, and a projection optical system that projects the intermediate image screen onto the glass.

  The projection unit according to the present invention is characterized in that a correction optical system for correcting an image projected by the projector is arranged between the projection unit and the intermediate screen.

  The projection unit according to the present invention is characterized in that the projection optical system is a concave mirror.

The projector according to the present invention includes a projection unit that projects an image, and displays the image projected by the projection unit by reflecting the image on glass, the first main surface, and the first A microlens array including a plurality of unit microlenses on the first main surface, and an image projected by the projection unit on the microlens array. The image forming apparatus includes an intermediate image screen that forms an image and a projection optical system that projects the intermediate image screen onto the glass.

  In the projector according to the aspect of the invention, a correction optical system that corrects an image projected by the projection unit may be disposed between the projection unit and the intermediate screen.

  The projector according to the present invention is characterized in that the projection optical system is a concave mirror.

  According to the projection unit of the present invention, the intermediate image screen provided with the microlens array focuses the image light of the image projected by the projector in an appropriate viewing angle, and concentrates the image light. Since the efficiency is achieved, the image projected by the projector can be projected onto general glass having a reflectance of 10% or less.

  Further, according to the projector according to the present invention, the intermediate image screen provided with the microlens array focuses the image light rays of the image projected by the projection unit in an appropriate viewing angle without being wasted. Since high efficiency is achieved, the image projected by the projection unit can be transferred to general glass having a reflectance of 10% or less.

It is a figure which shows typically the projector 10 with which the projection unit 100 which concerns on embodiment of this invention was attached. FIG. 5 is a perspective view of an intermediate image screen 50 according to an embodiment of the present invention, and a portion inserted by a dotted line is an enlarged view of a unit microlens 55. It is the figure which looked at the micro lens array 57 extended in the 1st direction and the 2nd direction from the z-axis direction. It is a figure explaining the effect of the correction of the laser beam by the condenser lens. It is a figure which shows typically the projector 10 with which the projection unit 100 which concerns on other embodiment of this invention was attached. FIG. 6 is a perspective view of an intermediate image screen 50 used in another embodiment of the present invention, and a portion inserted by a dotted line is an enlarged view of a unit microlens 55. It is a figure explaining the effect of the correction | amendment of the laser beam by the convex lens structure part 60 of the intermediate | middle image screen. It is a perspective view of the intermediate image screen 50 used in other embodiment of this invention. It is the figure which looked at the micro lens array 57 extended in the 1st direction and the 2nd direction from the z-axis direction of the intermediate | middle image screen 50 used in other embodiment of this invention. It is the figure which looked at the micro lens array 57 extended in the 1st direction and the 2nd direction from the z-axis direction of the intermediate | middle image screen 50 used in other embodiment of this invention. It is the figure which looked at the micro lens array 57 extended in the 1st direction and the 2nd direction from the z-axis direction of the intermediate | middle image screen 50 used in other embodiment of this invention. It is the figure which looked at the micro lens array 57 extended in the 1st direction and the 2nd direction from the z-axis direction of the intermediate | middle image screen 50 used in other embodiment of this invention. It is the figure which looked at the micro lens array 57 extended in the 1st direction and the 2nd direction from the z-axis direction of the intermediate | middle image screen 50 used in other embodiment of this invention. It is the figure which looked at the micro lens array 57 extended in the 1st direction and the 2nd direction from the z-axis direction of the intermediate | middle image screen 50 used in other embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram schematically showing a projector 10 to which a projection unit 100 according to an embodiment of the present invention is attached.

  Coordinates indicating the arrangement of the projector 10 and the projection unit 100 are defined by xyz three-dimensional orthogonal coordinates shown in FIG. For example, the image light beam constituting the video projected from the projector 10 is light emitted toward the direction parallel to the x axis. Further, it is assumed that the optical axes of the projector 10, the condenser lens 20, and the intermediate image screen 50 are in a direction parallel to the z direction.

  In this embodiment, it is assumed that the projector 10 is attached to the projector 10 that is generally commercially available, but the projector 10 (projection unit) and the projection unit 100 are combined again. It is also possible to view the configuration as a single projector. Based on such a viewpoint, the scope of claims is described in which the category is “projector”. At this time, the projector 10 is expressed as a “projection unit” again.

  In the present embodiment, a projector 10 that is generally commercially available is used with the projection unit 100 attached, and an image projected by the projector 10 is displayed by being reflected on the glass 110 having a reflectance of 10% or less. Assumes that.

  Further, in the present embodiment, the projection image from the projection unit 100 is displayed on the portion of the glass 110 that is shaded in FIG.

  From the projector 10 that projects an image, image light rays of the image to be projected are emitted in a direction parallel to the z axis. The image light beam emitted from the projector 10 enters the condenser lens 20.

  The condenser lens 20 corrects image light incident on the intermediate image screen 50 as a correction optical system. However, the condenser lens 20 is not an essential constituent element, and the condenser lens 20 can be replaced with another optical member.

  The intermediate image screen 50 is an optical member made of a transparent substrate having a predetermined transparency or higher. The intermediate image screen 50 can be configured by molding using a transparent organic resin material, or can be configured by using an inorganic material such as transparent glass.

  However, since the intermediate image screen 50 is disposed so as to be exposed to the light and heat of the projector 10, it is preferable that the intermediate image screen 50 has heat resistance. In the case where an organic resin material is used, COP (sculoolefin polymer) or PC is used. A high heat resistant resin such as (polycarbonate) may be used.

  FIG. 2 is a perspective view of the intermediate image screen 50 according to the embodiment of the present invention, and a portion inserted by a dotted line is an enlarged view of the unit microlens 55. 2 is a view of the intermediate image screen 50 as viewed from the direction A in FIG. 2, and an enlarged view of the unit microlens 55 is an xyz orthogonal coordinate in the portion inserted by the dotted line. The directional relationship is determined by the system.

  Here, the direction of the axis parallel to the x axis is defined as the first direction, and the direction of the axis parallel to the y axis is defined as the second direction (orthogonal relationship with the first direction).

Under the definition as described above, the intermediate image screen 50 is opposed to the first main surface 51, the first main surface 51 extending in the first direction, the second direction orthogonal to the first direction, and the first main surface 51. 1 direction and the 2nd main surface 52 extended in the said 2nd direction.

  The first main surface 51 of the intermediate image screen 50 is provided with a microlens array 57 in which a plurality of unit microlenses 55 are periodically arranged. FIG. 3 is a view of the microlens array 57 spreading in the first direction and the second direction as seen from the z-axis direction. As shown in the figure, in the intermediate image screen 50 according to the present embodiment, a unit microlens 55 having a square shape with one side having a length d when viewed from the z-axis direction is used.

Each unit microlens 55 is a spherical lens, and has a spherical surface with a radius of curvature R _{1 in} the first direction and a spherical surface with a radius of curvature R _{2 in} the second direction.

The radius of curvature R ₁ in the first direction and the radius of curvature R ₂ in the second direction of each unit microlens 55 can be made equal, but are preferably different. In general, the aspect ratio of the image information displayed by the projector 10 and the projection unit 100 is different, and the luminance reduction in the peripheral portion of the image is suppressed from the periphery of the upper and lower end portions of the image and the periphery of the left and right end portions of the image. This is because the radius of curvature R ₁ in the first direction and the radius of curvature R _{2 in} the second direction of each unit microlens 55 should be different from each other.

Furthermore, in general, taking into account that the image information displayed by the projector 10 and the projection unit 100 is horizontally long, the curvature R _{1 of} each unit microlens 55 in the first direction is:
It is preferably larger than the radius of curvature R _{2 in} the second direction.

  In the present embodiment, the condenser lens 20 is corrected so that the incident angle of the image light beam of the image incident on the unit microlens 55 constituting the microlens array 57 falls within the opening angle α of the unit microlens 55. Do. FIG. 4 is a diagram for explaining the effect of correcting the laser beam by the condenser lens 20. As shown in FIG. 4, the image light ray of the image incident on each unit microlens 55 by the refraction action of the condenser lens 20 falls within the opening angle α of the unit microlens 55.

  The microlens array 57 is configured by an array of a plurality of unit microlenses 55. Each unit microlens 55 receives image light rays corrected by the condenser lens 2 and forms an image on the back surface thereof. The microlens array 57 of the intermediate image screen 50 concentrates and forms an image light beam of the image projected by the projector 10 within an appropriate viewing angle without waste.

  The image formed by the microlens array 57 of the intermediate image screen 50 is reflected by the first concave mirror 81 and the second concave mirror 82 used as a projection optical system and projected onto the glass 110.

  On the glass 110, the projected image is displayed by being reflected, and this display can be viewed from the viewpoint E.

  In the present invention, the projection optical system only needs to be able to project an image formed by the microlens array 57 of the intermediate image screen 50 onto the glass 110, and the first concave mirror 81 and the second concave mirror 82 are required. Other optical members may be used.

According to the projection unit 100 according to the present invention as described above, the intermediate image screen 50 provided with the microlens array 57 allows the image light beam of the image projected by the projector 10 to be in an appropriate viewing angle without waste. Since the image is concentrated and high efficiency is achieved, the image projected by the projector 10 can be projected on general glass having a reflectance of 10% or less.

  Next, another embodiment of the present invention will be described. In the first embodiment, the condenser lens 20 is used as the correction optical system, thereby correcting the image light beam emitted from the projector 10 and incident on the intermediate image screen 50.

  On the other hand, in the second embodiment, the convex lens structure 60 provided on the second main surface 52 of the intermediate image screen 50 is used as the correction optical system.

  FIG. 5 is a diagram schematically showing a projector 10 to which a projection unit 100 according to another embodiment of the present invention is attached. FIG. 6 is a perspective view of an intermediate image screen 50 used in another embodiment of the present invention, and a portion inserted by a dotted line is an enlarged view of the unit microlens 55. Since the structure of the first main surface 51 of the intermediate image screen 50 is the same as that of the previous embodiment, the description thereof is omitted.

Here, the convex lens structure portion 60 of the intermediate image screen 50 according to the present embodiment will be described in detail. The convex lens structure portion 60 of the intermediate image screen 50 according to the present embodiment is a spherical lens having a spherical surface with a radius of curvature R _{3 in} the first direction and a spherical surface with a radius of curvature R _{4 in} the second direction. Yes.

As in the case of the unit micro lens 55, the radius of curvature R ₃ of the convex lens structure 60 in the first direction.
The radius of curvature R ₄ in the second direction can be made equal, but is preferably different. In general, the aspect ratio of the image information displayed by the projector 10 and the projection unit 100 is different, and the luminance reduction in the peripheral portion of the image is suppressed from the periphery of the upper and lower end portions of the image and the periphery of the left and right end portions of the image. The curvature radius R _{3 in} the first direction of the convex lens structure 60,
This is because the curvature radius R _{4 in} the second direction should be different.

Furthermore, in general, taking into account that the image information displayed by the projector 10 and the projection unit 100 is horizontally long, the curvature R _{3 in} the first direction of the convex lens structure 60 is the curvature radius R in the second direction. It is preferably greater than ₄ .

  The convex lens structure section 60 performs correction so that the incident angle of the laser light incident on the unit microlens 55 constituting the microlens array 57 falls within the opening angle α of the unit microlens 55. FIG. 7 is a diagram for explaining the effect of laser light correction by the convex lens structure section 60 of the intermediate image screen 50. As shown in FIG. 7, the laser light incident on each unit microlens 55 falls within the opening angle α of the unit microlens 55 by the refracting action of the convex lens structure portion 60.

  According to the second embodiment as described above, the same effect as that of the first embodiment can be enjoyed, and the condenser lens 20 can be reduced as a component compared to the first embodiment. The cost of the projection unit 100 in which 50 is incorporated can be suppressed, and the optical characteristics of the projection unit 100 can be prevented from being deteriorated.

  Next, another embodiment of the present invention will be described. Since the third embodiment is different from the second embodiment only in the configuration of the convex lens structure 60 provided on the second main surface 52 of the intermediate image screen 50, this point will be described below.

FIG. 8 is a perspective view of an intermediate image screen 50 used in another embodiment of the present invention. In the second embodiment, it has been described that the curvature R _{3 in} the first direction of the convex lens structure 60 is preferably larger than the curvature radius R _{4 in} the second direction as the convex lens structure 60 of the intermediate image screen 50. In the present embodiment, this is further advanced so that the radius of curvature R ₃ in the first direction of the convex lens structure portion 60 is infinite.

In general, since the image information displayed by the projector 10 and the projection unit 100 is horizontally long, a decrease in luminance at the periphery of the image is more likely to occur at the periphery of the left and right edges of the image than at the periphery of the upper and lower edges of the image. Therefore, the curvature radius R ₃ in the first direction of the convex lens structure 60 is set to infinity, and in particular, a decrease in luminance around the left and right end portions of the image is suppressed.

  Also by such 3rd Embodiment, the effect similar to 2nd Embodiment can be enjoyed.

  Next, another embodiment of the present invention will be described. Since the fourth embodiment is different from the first embodiment only in the configuration of the microlens array 57 provided on the first main surface 51 of the intermediate image screen 50, this point will be described below.

  FIG. 9 is a view of an intermediate image screen 50 used in another embodiment of the present invention, as viewed from the z-axis direction, with a microlens array 57 extending in the first direction and the second direction.

  The unit microlenses 55 of the microlens array 57 provided on the first main surface 51 of the intermediate image screen 50 according to the first embodiment are square when viewed from the z-axis direction, but according to the fourth embodiment. The unit microlenses 55 of the microlens array 57 provided on the first main surface 51 of the intermediate image screen 50 are configured as rectangles when viewed from the z-axis direction.

Here, when the length d ₁ in the first direction of the unit micro lens 55 is compared with the length d ₂ in the second direction, it is preferable that d ₁ <d ₂ . This is because the image information displayed by the projector 10 and the projection unit 100 is generally horizontally long.

Also in this embodiment, taking into account that the image information displayed by the projection unit 100 is horizontally long, the curvature R _{1 in} the first direction of each unit microlens 55 is the curvature radius R _{2 in} the second direction. Larger is preferred.

  According to the embodiment as described above, the same effect as that of the previous embodiment can be obtained.

  Next, another embodiment of the present invention will be described. The fifth embodiment is different from the first embodiment only in the configuration of the microlens array 57 provided on the first main surface 51 of the intermediate image screen 50. This will be described below.

  FIG. 10 is a view of an intermediate image screen 50 used in another embodiment of the present invention, as viewed from the z-axis direction, with a microlens array 57 extending in the first direction and the second direction.

  The unit microlenses 55 of the microlens array 57 provided on the first main surface 51 of the intermediate image screen 50 according to the first embodiment are square when viewed from the z-axis direction, but according to the fourth embodiment. The unit microlenses 55 of the microlens array 57 provided on the first main surface 51 of the intermediate image screen 50 are configured as regular hexagons when viewed from the z-axis direction.

Also in this embodiment, taking into account that the image information displayed by the projector 10 and the projection unit 100 is horizontally long, the curvature R _{1 of} each unit microlens 55 in the first direction is the curvature radius R in the second direction. Preferably it is greater than ₂ .

  According to the embodiment as described above, the same effect as that of the previous embodiment can be obtained.

  Next, another embodiment of the present invention will be described. Since the sixth embodiment is different from the first embodiment only in the configuration of the microlens array 57 provided on the first main surface 51 of the intermediate image screen 50, this point will be described below.

  FIG. 11 is a view of an intermediate image screen 50 used in another embodiment of the present invention, as viewed from the z-axis direction, with a microlens array 57 extending in the first direction and the second direction.

  The unit microlenses 55 of the microlens array 57 provided on the first main surface 51 of the intermediate image screen 50 according to the first embodiment are square when viewed from the z-axis direction, but according to the fourth embodiment. The unit microlenses 55 of the microlens array 57 provided on the first main surface 51 of the intermediate image screen 50 are configured as hexagons that are not regular hexagons when viewed from the z-axis direction.

  Here, it is preferable that the hexagon forming the unit micro lens 55 is a horizontally long hexagon in which only the side parallel to the second direction is longer than the length of the other side. This is because the image information displayed by the projector 10 and the projection unit 100 is generally horizontally long.

Also in this embodiment, taking into account that the image information displayed by the projector 10 and the projection unit 100 is horizontally long, the curvature R _{1 in} the first direction of each unit microlens 55 is the curvature in the second direction. it is preferably larger than the radius R _2.

  According to the embodiment as described above, the same effect as that of the previous embodiment can be obtained.

  Next, another embodiment of the present invention will be described. Since the seventh embodiment is different from the first embodiment only in the configuration of the microlens array 57 provided on the first main surface 51 of the intermediate image screen 50, this point will be described below.

  FIG. 12 is a view of an intermediate image screen 50 used in another embodiment of the present invention, as viewed from the z-axis direction, with a microlens array 57 extending in the first direction and the second direction.

  The unit microlenses 55 of the microlens array 57 provided on the first main surface 51 of the intermediate image screen 50 according to the first embodiment are square when viewed from the z-axis direction, but according to the fourth embodiment. The unit micro lens 55 of the micro lens array 57 provided on the first main surface 51 of the intermediate image screen 50 is configured as a circle when viewed from the z-axis direction.

Also in this embodiment, taking into account that the image information displayed by the projector 10 and the projection unit 100 is horizontally long, the curvature R _{1 of} each unit microlens 55 in the first direction is the curvature radius R in the second direction. Preferably it is greater than ₂ .

  According to the embodiment as described above, the same effect as that of the previous embodiment can be obtained.

  Next, another embodiment of the present invention will be described. Since the eighth embodiment is different from the first embodiment only in the configuration of the microlens array 57 provided on the first main surface 51 of the intermediate image screen 50, this point will be described below.

  FIG. 13 is a view of an intermediate image screen 50 used in another embodiment of the present invention, as viewed from the z-axis direction, with a microlens array 57 extending in the first direction and the second direction.

  The unit microlenses 55 of the microlens array 57 provided on the first main surface 51 of the intermediate image screen 50 according to the first embodiment are square when viewed from the z-axis direction, but according to the fourth embodiment. The unit microlens 55 of the microlens array 57 provided on the first main surface 51 of the intermediate image screen 50 is configured as an ellipse when viewed from the z-axis direction.

Here, an elliptical shape constituting the unit microlens 55 is a horizontally long elliptical shape in which the long axis φ ₁ is parallel to the second direction and the short axis φ ₂ is parallel to the first direction. Preferably there is. This is because the image information displayed by the projector 10 and the projection unit 100 is generally horizontally long.

Also in this embodiment, taking into account that the image information displayed by the projector 10 and the projection unit 100 is horizontally long, the curvature R _{1 in} the first direction of each unit microlens 55 is the curvature in the second direction. it is preferably larger than the radius R _2.

  According to the embodiment as described above, the same effect as that of the previous embodiment can be obtained.

  Next, another embodiment of the present invention will be described. Since the ninth embodiment is different from the first embodiment only in the configuration of the microlens array 57 provided on the first main surface 51 of the intermediate image screen 50, this point will be described below.

  FIG. 14 is a view of an intermediate image screen 50 used in another embodiment of the present invention, as viewed from the z-axis direction, with a microlens array 57 extending in the first direction and the second direction.

  The unit microlenses 55 of the microlens array 57 provided on the first main surface 51 of the intermediate image screen 50 according to the first embodiment are square when viewed from the z-axis direction, but according to the fourth embodiment. The unit microlens 55 of the microlens array 57 provided on the first main surface 51 of the intermediate image screen 50 is configured as an oval when viewed from the z-axis direction.

  Here, the oval shape constituting the unit microlens 55 is preferably an oblong oval shape in which the oval linear portion is parallel to the second direction. This is because the image information displayed by the projector 10 and the projection unit 100 is generally horizontally long.

Also in this embodiment, taking into account that the image information displayed by the projector 10 and the projection unit 100 is horizontally long, the curvature R _{1 in} the first direction of each unit microlens 55 is the curvature in the second direction. it is preferably larger than the radius R _2.

  According to the embodiment as described above, the same effect as that of the previous embodiment can be obtained.

The present invention is not limited to the first to ninth embodiments, and embodiments configured by appropriately combining the configurations of the respective embodiments also fall within the scope of the present invention.

  As described above, according to the projection unit 100 according to the present invention, the intermediate image screen 50 provided with the microlens array concentrates the image light beam of the image projected by the projector 10 within an appropriate viewing angle without waste. Since the image is formed and high efficiency is achieved, the image projected by the projector 10 can be transferred to general glass having a reflectance of 10% or less.

  Further, according to the projector according to the present invention, the intermediate image screen 50 provided with the microlens array concentrates and forms the image light beam of the image projected by the projection unit within an appropriate viewing angle without waste. In addition, since high efficiency is achieved, it is possible to transfer an image projected by the projection unit onto general glass having a reflectance of 10% or less.

DESCRIPTION OF SYMBOLS 10 ... Projector 20 ... Condenser lens 50 ... Intermediate image screen 51 ... 1st main surface 52 ... 2nd main surface 55 ... Unit micro lens 57 ... Micro lens array 60- ..Convex lens structure part 81 ... first concave mirror 82 ... second concave mirror 100 ... projection unit 110 ... glass

Claims (6)

A projection unit that is used by being attached to a projector that projects an image, and that displays the image projected by the projector by reflecting it on glass,
A microlens array having a first main surface and a second main surface opposite to the first main surface, the microlens array including a plurality of unit microlenses being provided on the first main surface; An intermediate image screen on which an image projected by the projector is formed;
A projection unit comprising: a projection optical system that projects the intermediate image screen onto the glass. The projection unit according to claim 1, wherein a correction optical system that corrects an image projected by the projector is disposed between the projection unit and the intermediate screen. The projection unit according to claim 1, wherein the projection optical system is a concave mirror. A projector having a projection unit for projecting an image, and displaying the image projected by the projection unit by reflecting the image on glass;
A microlens array having a first main surface and a second main surface opposite to the first main surface, the microlens array including a plurality of unit microlenses being provided on the first main surface; An intermediate image screen on which an image projected by the projection unit is formed;
And a projection optical system for projecting the intermediate image screen onto the glass. The projector according to claim 4, wherein a correction optical system that corrects an image projected by the projection unit is disposed between the projection unit and the intermediate screen. 6. The projector according to claim 4, wherein the projection optical system is a concave mirror.

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