WO2018042561A1

WO2018042561A1 - Rod integrator holding device and projector

Info

Publication number: WO2018042561A1
Application number: PCT/JP2016/075525
Authority: WO
Inventors: 直樹増田
Original assignee: Ｎｅｃディスプレイソリューションズ株式会社
Priority date: 2016-08-31
Filing date: 2016-08-31
Publication date: 2018-03-08
Also published as: CN208621807U

Abstract

The present invention suppresses breakage of an edge portion (corner section) of an end surface of a rod integrator. This rod integrator holding device has plates (1, 2) that sandwich both end surfaces of a prismatic rod integrator (6). A plate (1) has bent sections (11, 12) extending in the long side direction of the plate.

Description

Rod integrator holding device and projector

The present invention relates to a holding device for holding a rod integrator represented by a light tunnel or a rod lens, and a projector using the holding device.

The projector includes a light source, an image forming element that spatially modulates light from the light source to form an image, and a projection lens that projects an image formed by the image forming element on a screen. The image forming element is a liquid crystal panel or DMD (digital micromirror device), and has a quadrangular image forming surface. In order to irradiate light from a light source uniformly and efficiently onto the image forming surface, a rod integrator is used.
The rod integrator is provided with a quadrangular prism-shaped light guide section, and is configured such that light incident on the light guide section is repeatedly reflected on the side surface and proceeds so that the light intensity distribution in the exit surface becomes uniform. The exit surface of the light guide unit forms a rectangular surface light source, and light from the surface light source is irradiated onto the image forming surface using a telecentric illumination optical system. The image forming surface of the image forming element is disposed at the imaging position of the illumination optical system.
What is provided with a solid light guide made of a transparent material such as glass is called a rod or a rod lens, and what is provided with a hollow light guide made by bonding four mirrors together is a light tunnel. being called.

As a structure for holding the rod integrator, a structure in which the two ends of the rod integrator are sandwiched between two plates is generally used. Patent Document 1 describes a rod lens holding member including a holder main body that accommodates a rod lens, and first and second plates that sandwich both end surfaces of the rod lens.
The holder body includes a base and first and second side walls that are provided on the base at predetermined intervals and face each other. The base and the first and second side walls are provided so as to surround the side surface of the rod lens. Each of the first and second side walls includes a screw hole for fixing the first plate to the first end surface which is the end portion on the incident side, and second on the second end surface which is the end portion on the emission side. Screw holes for fixing the plate.

The first plate has an opening in the central portion, and a supporting surface that supports the incident end surface of the rod lens in the opening portion. Of the two end portions in the longitudinal direction of the first plate, one end is fixed to the first end surface of the first side wall with a screw, and the other end is screwed to the first end surface of the second side wall. It is fixed with.
The second plate has an opening in the central portion, and a support surface that supports the exit end surface of the rod lens in the opening portion. Of the two end portions in the longitudinal direction of the second plate, one end is fixed to the second end face of the first side wall with a screw, and the other end is screwed to the second end face of the second side wall. It is fixed with.

JP 2007-298600 A

In the holding structure described in Patent Document 1, since the end surface of the rod lens is pressed by the support surface at the central portion of the plate, the plate is deformed into an arcuate shape. In this case, the curved surface (concave surface) of the plate may be in contact with the edge portion (corner portion) of the end surface of the rod lens, and stress may concentrate on the corner portion and be damaged.
The same problem occurs even if a light tunnel is used instead of the rod lens.

An object of the present invention is to provide a rod integrator holding device and a projector using the rod integrator holding device that can prevent the edge portion (corner portion) of the end surface of the rod integrator from being damaged.

In order to achieve the above object, according to one aspect of the present invention, the first and second plates sandwiching both end faces of a prismatic rod integrator are provided, and the first plate is the first plate. There is provided a rod integrator holding device having a first bend extending in the longitudinal direction.

According to another aspect of the present invention, the rod integrator holding device, the light source, the rod integrator held by the rod integrator holding device, and light from the light source is incident via the rod integrator, and the incident A projector is provided that includes an image forming element that spatially modulates the light and forms an image, and a projection lens that projects an image formed by the image forming element.

It is a figure which shows the structure of the rod integrator holding apparatus which is the 1st Embodiment of this invention, Comprising: (a) is a perspective view, (b) is the disassembled perspective view. 1A and 1B are views of a rod integrator holding device according to a first embodiment of the present invention viewed from an angle different from that in FIG. 1, in which FIG. 1B is a perspective view, and FIG. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the rod integrator holding device which is the 1st Embodiment of this invention, (a) is a front view, (b) is the side view seen from the left side (injection side), (c) is the right side (incident) Side view seen from the side), (d) is a top view. It is an enlarged view of the round frame B of (b) of FIG. It is an enlarged view of the round frame A of (c) of FIG. It is an enlarged view of the round frame C of (a) of FIG. It is a perspective view which shows the structure of the rod integrator holding device which is the 2nd Embodiment of this invention. It is a schematic diagram showing an example of a projector to which the rod integrator holding device of the present invention is applied. It is a schematic diagram which shows another example of the projector to which the rod integrator holding apparatus of this invention is applied.

Next, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
FIG. 1 to FIG. 3 are diagrams showing a configuration of a rod integrator holding device according to the first embodiment of the present invention. 1A is a perspective view, and FIG. 1B is an exploded perspective view thereof. 2B is a perspective view when viewed from an angle different from that in FIG. 1, and FIG. 2B is an exploded perspective view thereof. 3A is a front view, FIG. 3B is a side view seen from the left side (exit side), FIG. 3C is a side view seen from the right side (incident side), and FIG. 3D is a top view.
Please refer to FIG. 1 to FIG. The rod integrator holding device includes two

plates

1 and 2, a pressing member 3, a holder portion 4, and fixing

members

5a and 5b.

The holder part 4 has a base plate 40 and side walls 41 to 44. The side walls 41 to 44 are integral and constitute one holding member for holding the light tunnel 6 as a whole. The

side walls

42 and 43 are provided on the base plate 40 so as to be perpendicular to the plate surface. The

side walls

41 and 42 are provided on both sides of the side wall 43 so as to face each other. The

side walls

41 and 42 are parallel to each other, and both are provided at an angle of about 90 ° with respect to the side wall 43. The side wall 43 is provided with an insertion hole 43a for fixing the pressing member 3 and support

members

43b and 43c.
The side wall 44 is provided so as to form an angle of 90 ° with each of the side walls 41 to 43. The

side walls

41 and 42 are located at both ends of the side wall 44. The side wall 44 includes

support portions

44a and 44b, screw holes 44c, and protrusions 44d. The

support portions

44 a and 44 b are provided at a predetermined interval and support the lower surface of the light tunnel 6. The screw hole 44c and the two protrusions 44d located on both sides thereof are for positioning the pressing member 3, and are provided between the

support portions

44a and 44b.

The pressing member 3 includes a contact portion 31 and fixing

portions

32 and 33 provided at both ends of the contact portion 31. The fixing portion 33 includes a protruding portion, and the protruding portion is fitted into the insertion hole 43 a to fix one end of the abutting portion 31 to the side wall 43. With the

support portions

44 a and 44 b supporting the lower surface of the light tunnel 6, the contact portion 31 presses the two side surfaces (upper surface and front surface) of the light tunnel 6. The other end of the contact portion 31 is fixed to the side wall 43 by fixing the fixing portion 32 to the screw hole 44 c with the screw 34. The fixing portion 32 includes two holes 32a for positioning, and the pressing member 3 is positioned with respect to the side wall 44 by fitting each protrusion 44d into each hole 32a. The side surface of the light tunnel 6 can be supported by the

support members

43 b and 43 c of the side wall 43, the

support portions

44 a and 44 b of the side wall 44, and the contact portion 31 of the pressing member 3.

The plate 1 is fixed to the outer surface 41 a of the side wall 41. The side wall 41 is provided with an opening 41d at the center, and on the surface 41a, positioning

protrusions

41b and 41c of the plate 1 are provided above and below the opening 41d. The upper end portion and the lower end portion of the side wall 41 each have an L-shaped structure for fitting the fixing

members

5a and 5b. The fixing

members

5a and 5b are U-shaped spring members. Stainless steel or the like is used as the material of the fixing

members

5a and 5b. The fixing member 5 a sandwiches the upper end of the plate 1 and the upper end of the side wall 41, and the fixing member 5 b sandwiches the lower end of the plate 1 and the lower end of the side wall 41, thereby fixing the plate 1 to the side wall 41.
The plate 1 has an opening 13 at the center, and has bent

portions

11 and 12 extending on both sides of the opening 13 in the longitudinal direction of the plate. Two

holes

14a and 14b are provided on the upper and lower sides of the opening 13, and the plate 1 can be positioned with respect to the side wall 41 by fitting the

protrusions

41b and 41c into the

holes

14a and 14b.

The plate 2 is fixed to the outer surface 42a of the side wall 42. The side wall 42 is provided with an opening 42d in the central portion, and

positioning projections

42b and 42c of the plate 2 are provided on the surface 42a vertically with the opening 42d interposed therebetween. On the surface 42a, two

pedestals

42e and 42f for determining a reference surface are provided above and below the opening 42d. Screw holes for fixing the plate 2 are provided in the

pedestals

42e and 42f. 42e-1 and 42f-1 are provided. The opening 42d of the side wall 42 faces the opening 41d of the side wall 41, and the light tunnel 6 is disposed so that both end portions thereof penetrate the

openings

41d and 42d.

The plate 2 has an opening 21 at the center. Two

holes

22 a and 22 c are provided above the opening 21, and two

holes

22 b and 22 d are provided below the opening 21. The plate 2 can be positioned with respect to the side wall 42 by fitting the projection 42b into the hole 22a and fitting the projection 42c into the hole 22b. The plate 2 is fixed to the

bases

42e and 42f of the side wall 42 by screwing the

screws

23a and 23b into the screw holes 42e-1 and 42f-1 through the

holes

22c and 22d, respectively. The

screws

23a and 23b, the

holes

22c and 22d, and the screw holes 42e-1 and 42f-1 are plate fixing members that fix the plate 2 to the side wall 42. In order to increase the rigidity of the plate 2, the plate fixing member is desirably provided in the vicinity of the outer peripheral portion of the opening 21.

The

plates

1 and 2 sandwich the both end surfaces of the light tunnel 6 while being fixed to the

side walls

41 and 42. The incident end surface of the light tunnel 6 is in contact with the outer peripheral surface of the opening 13 of the plate 1, and the emission end surface of the light tunnel 6 is in contact with the outer peripheral surface of the opening 21 of the plate 2. It is desirable that the

plates

1 and 2 are made of a material having glitter (for example, glitter aluminum).

FIG. 4 is a diagram for explaining the positional relationship between the exit end face of the light tunnel 6 and the opening 21 of the plate 2, and is an enlarged view of a round frame B in FIG. 3 (b). The exit end face of the light tunnel 6 includes an annular end face 6a composed of the respective edge faces of the four mirrors. The opening 21 of the plate 2 is larger than the inner diameter of the end surface 6a and smaller than the outer shape of the end surface 6a. In the present embodiment, the opening 21 is larger than the inner diameter of the end surface 6a by half the width (mirror thickness) d1 of the end surface 6a. The size of the opening 21 is appropriately set based on the thickness of the plate 2, the width d1 of the end face 6a, the emission angle of the light tunnel 6, and the like so that no vignetting of the emitted light occurs.

FIG. 5 is a diagram for explaining the positional relationship between the incident end face of the light tunnel 6 and the opening 13 of the plate 1, and is an enlarged view of the round frame A in FIG. The incident end face of the light tunnel 6 includes an annular end face 6b composed of the edge faces of the four mirrors. The opening 13 of the plate 1 is larger than the inner diameter of the end surface 6b and smaller than the outer shape of the end surface 6b. In the present embodiment, the opening 13 is larger than the inner diameter of the end surface 6b by half of the width (mirror thickness) d2 of the end surface 6b. The size of the opening 13 is appropriately set based on the thickness of the plate 1, the width d2 of the end face 6b, the incident angle to the light tunnel 6, and the like so that no vignetting of incident light occurs.
By fixing the plate 2 to the

pedestals

42e and 42f that determine the reference plane, the exit end face of the light tunnel 6 that is in contact with the plate 2 can be used as the reference plane. FIG. 6 is an enlarged view of the round frame C in FIG. As shown in FIG. 6, the plate surface of the plate 2 is in contact with the surfaces of the

bases

42 e and 42 f, and the emission end surface of the light tunnel 6 is in contact with the plate surface of the plate 2. When the surfaces of the

pedestals

42e and 42f are used as the reference surface, the exit end surface of the light tunnel 6 also coincides with the reference surface.

In the rod integrator holding device of the present embodiment, when the light tunnel 6 is held by the holder portion 4, first, the plate 2 is fixed to the

pedestals

42 e and 42 f of the side wall 42, and the exit end face of the light tunnel 6 is the opening 21 of the plate 2. Abuts on the surface on which is formed (see FIG. 4). Next, the incident end face of the light tunnel 6 is brought into contact with the face on which the opening 13 of the plate 1 is formed (see FIG. 5). In this state, the plate 1 is fixed to the side wall 41 using the fixing

members

5a and 5b. To do. Finally, the side surface of the light tunnel 6 is fixed using the pressing member 3.

According to the rod integrator holding device of the present embodiment, the following operational effects can be obtained.
The incident end surface of the light tunnel 6 protrudes outward from the surface 41 a of the side wall 41, and the fixing

members

5 a and 5 b are attached to both ends of the plate 1 with the incident end surface of the light tunnel 6 in contact with the central portion of the plate 1. Push toward the surface 41a side. In this case, a force that causes the plate 1 to deform in an arcuate shape is applied. In the present embodiment, the plate 1 has bent

portions

11 and 12 extending in the longitudinal direction of the plate on both sides of the opening 13. The angle formed between the

bent portions

11 and 12 and the plate surface of the plate 1 is about 45 degrees. This angle may be 25 degrees or more. Of course, it may be vertical (90 degrees). Since the rigidity of the plate 1 is enhanced by the

bent portions

11 and 12, the plate 1 is not deformed into an arcuate shape. Therefore, since the plate 1 and the incident end face of the light tunnel 6 can be brought into surface contact, there is no problem that stress concentrates on the edge portion (corner portion) of the incident end face of the light tunnel 6 and breaks.

As a method for increasing the rigidity of the plate, there are a method for increasing the thickness of the plate (hereinafter referred to as method A) and a method for fixing a portion near the opening of the plate to the side wall (hereinafter referred to as method B). . However, when the rigidity of the plate 1 is increased by applying the method A or the method B instead of the

bent portions

11 and 12, the following problems occur.
(When Method A is applied)
In a projector equipped with a rod integrator holding device, light from a light source is collected on the incident end face of the light tunnel 6 by a condenser lens. The light from the condenser lens passes through the opening 13 of the plate 1 and enters the incident end face of the light tunnel 6. When the thickness of the plate 1 increases, a part of the light incident on the incident end face of the light tunnel 6 is blocked by the opening 13, and as a result, the brightness at the exit end face of the light tunnel 6 (the brightness of the surface light source) decreases. To do.

(When Method B is applied)
Light from the condensing lens passes through the opening 13 of the plate 1 and enters the incident end face of the light tunnel 6, but part of the light is also irradiated to the outer peripheral portion of the opening 13. Since the intensity of the light from the condensing lens is high, when stainless steel or the like is used as the material of the plate 1, the portion of the opening 13 may be heated and melted by light irradiation. For this reason, bright aluminum is used as the material of the plate 1.
The fixing

members

5a and 5b are made of a material having no glitter such as stainless steel. For this reason, if the vicinity of the opening 13 of the plate 1 is fixed by the fixing

members

5a and 5b, the fixing

members

5a and 5b may be heated and melted by light irradiation.
The above is description of the effect about the plate 1 of the light tunnel 6 on the incident surface side.

Also on the plate 2 on the exit surface side of the light tunnel 6, a force that deforms into a bow shape works. In the present embodiment, the rigidity of the plate 2 is increased by fixing the vicinity of the opening 21 of the plate 2 with

screws

23a and 23b, and the plate 2 is not deformed into an arcuate shape. Therefore, since the plate 2 and the exit end face of the light tunnel 6 can be brought into surface contact, there is no problem that the stress concentrates on the edge portion (corner) of the exit end face of the light tunnel 6 and breaks.
In addition, since the plate 2 is disposed on the exit side of the light tunnel 6, there is no problem when the method B is applied.

(Second Embodiment)
FIG. 7 is a perspective view showing a rod integrator holding device according to the second embodiment of the present invention.
The rod integrator holding device of this embodiment is different from that of the first embodiment in that a plate 7 is used instead of the plate 2. Since the configuration other than the plate 7 is the same as that of the first embodiment, the description of the configuration is omitted here.

As shown in FIG. 7, the plate 7 has bent

portions

71 and 72 extending in the longitudinal direction of the plate 7. The portions other than the

bent portions

71 and 72 are basically the same as those of the plate 2 described in the first embodiment, but the

screws

23a and 23b are not in the vicinity of the opening 21 but fix both end portions of the plate 7. . The

bent portions

71 and 72 are provided on both sides of the opening 21. The angle formed between the

bent portions

71 and 72 and the plate surface of the plate 7 is about 45 degrees. This angle may be 25 degrees or more. Of course, it may be vertical (90 degrees).
According to the rod integrator holding device of the present embodiment, since the rigidity of the plate 7 is enhanced by the

bent portions

71 and 72 provided on both sides of the opening 21, the plate 7 does not deform into an arcuate shape. Therefore, since the plate 7 and the exit end face of the light tunnel 6 can be brought into surface contact, there is no problem that stress concentrates on the edge portion (corner) of the exit end face of the light tunnel 6 and breaks.

The rod integrator holding device of each embodiment explained above is an example of the present invention, and the composition can be changed suitably.
For example, in 1st Embodiment, although the plate 1 has the bending

parts

11 and 12, it is not limited to this. The plate 1 may have a structure including one of the

bent portions

11 and 12. Similarly, in 2nd Embodiment, although the plate 7 has the bending

parts

71 and 72, it is not limited to this. The plate 7 may have a structure including one of the

bent portions

71 and 72.

Further, instead of the light tunnel 6, a rod having a solid light guide portion made of a transparent material such as glass is used, and both end surfaces of the rod are sandwiched between the plate 1 and the plate 2 (or the plate 7). May be. However, in this case, the plate needs to be configured to hold the four corners of the end face of the rod.

(projector)
The projector of the present invention includes the above-described rod integrator holding device, a light source, a rod integrator held by the rod integrator holding device, and light from the light source is incident through the rod integrator, and the incident light is An image forming element that spatially modulates and forms an image; and a projection lens that projects an image formed by the image forming element.

The rod integrator holding device of the present invention can be applied to various projectors.
FIG. 8 is a schematic diagram showing an example of a projector to which the light pipe holding device of the present invention is applied.
Referring to FIG. 8, the projector includes a light source 100, a color wheel 101, a light tunnel 102, optical lenses 103a to 103c, mirrors 104a and 104b, a DMD 105, and a projection lens 106.

The light source 100 emits white light. As the light source 100, a xenon lamp or an ultrahigh pressure mercury lamp can be used. White light from the light source 100 is applied to the color wheel 101 via an optical lens (not shown).
The color wheel 101 includes a red transmissive area, a green transmissive area, and a blue transmissive area. By rotating the wheel, white light from the light source 100 is sequentially irradiated to the red transmissive area, the green transmissive area, and the blue transmissive area. . Of the white light, red light is transmitted through the red transmission region, green light is transmitted through the green transmission region, and blue light is transmitted through the blue transmission region. In the color wheel 101, red light (R light), green light (G light), and blue light (B light) are emitted in a time division manner.

Light (R, G, B) from the color wheel 101 is applied to the incident end face of the light tunnel 102 via an optical lens (not shown). The exit end face of the light tunnel 102 forms a surface light source that sequentially emits R light, G light, and B light.
Between the exit end face of the light tunnel 102 and the DMD 105,

optical lenses

103a and 103b,

optical mirrors

104a and 104b, and an optical lens 103c are arranged in this order. Light from the exit end face of the light tunnel 102 passes through the

optical lenses

103a and 103b and enters the optical mirror 104a.

The optical mirror 104a reflects the light that has passed through the

optical lenses

103a and 103b toward the optical mirror 104b. The optical mirror 104 b reflects the light from the optical mirror 104 a toward the DMD 105. The light from the optical mirror 104 b passes through the optical lens 103 and is irradiated on the DMD 105.
The

optical lenses

103 a, 103 b, and 103 c are telecentric illumination optical systems that irradiate light from a surface light source onto the image forming surface of the DMD 105. The image forming surface of the DMD 105 is disposed on the imaging surface of this telecentric illumination optical system.
The projection lens 106 projects an image formed on the image forming surface of the DMD 105 on a screen (not shown).
In the projector, the light tunnel 102 is held by the rod integrator holding device of the first or second embodiment described above.

FIG. 9 is a block diagram showing another example of a projector to which the rod integrator holding device of the present invention is applied.
The projector 1100 includes a light source 1101, an optical engine unit 1102, an image forming unit 1103, and a projection lens (projection optical system) 1104. The image forming unit 1103 includes display devices 1105 to 1107 that modulate light according to an image signal, and has a function of forming an image based on light emitted from the optical engine unit 1102. As the display devices 1105 to 1107, a digital micromirror device (DMD) that is a reflective display element or a liquid crystal panel may be used. The image forming unit 1103 includes three display devices 1105 to 1107 corresponding to red light, green light, and blue light. The projection lens 1104 has a function of projecting light emitted from the image forming unit 1103 onto a screen 1109 and displaying the image as an image.

In the projector, the rod integrator holding device of the present invention is disposed between the light source 1101 and the optical engine unit 1102. The rod integrator holding device holds a rod integrator such as a light tunnel or a rod lens.
As the light source 1101, a solid light source represented by a laser diode (LD) or the like, or a light source including a phosphor can be used, and a light source unit in which these light sources are combined can also be used.

1, 2 Plate 3 Holding member 4

Holder part

5a, 5b Fixing member 6

Light tunnel

11, 12 Bending part

Claims

A rod having first and second plates sandwiching both end faces of a prismatic rod integrator, wherein the first plate has a first bent portion extending in the longitudinal direction of the first plate. Integrator holding device.
The rod integrator holding device according to claim 1,
The first end surface that is the entrance surface of the both end surfaces of the rod integrator is in contact with the first plate,
The first plate includes a first opening for allowing light to enter the first end face, and the first bent portion is provided on both sides of the first opening. apparatus.
The rod integrator holding device according to claim 1 or 2,
The rod integrator holding device, wherein the second plate has a second bent portion extending in a longitudinal direction of the second plate.
In the rod integrator holding device according to claim 3,
A second end surface that is an emission surface of the both end surfaces of the rod integrator is in contact with the second plate,
The second plate includes a second opening through which light emitted from the second end surface passes, and the second bent portion is provided on both sides of the second opening. apparatus.
The rod integrator holding device according to claim 1 or 2,
Having a side wall to which the second plate is fixed;
A second end surface that is an emission surface of the both end surfaces of the rod integrator is in contact with the second plate,
The second plate includes a second opening through which light emitted from the second end surface passes, and is fixed to the outer peripheral portion of the second opening for fixing the second plate to the side wall. A rod integrator holding device comprising a member.
In the rod integrator holding device according to any one of claims 1 to 5,
The rod integrator holding device, wherein an angle formed by the plate surface of the first plate and the first bent portion is 45 degrees.
The rod integrator holding device according to claim 3 or 4,
The rod integrator holding device, wherein an angle formed by the plate surface of the second plate and the second bent portion is 45 degrees.
In the rod integrator holding device according to any one of claims 1 to 7,
The rod integrator holding device, wherein the rod integrator is a light tunnel.
In the rod integrator holding device according to any one of claims 1 to 7,
The rod integrator is a rod integrator holding device having a rod lens.
The rod integrator holding device according to any one of claims 1 to 9,
A light source;
A rod integrator held by the rod integrator holding device;
The light from the light source enters through the rod integrator, and an image forming element that spatially modulates the incident light to form an image;
And a projection lens that projects an image formed by the image forming element.