JP2009008808A - Optical unit and display device - Google Patents

Abstract

An object of the present invention is to prevent heat from a light shielding member interposed between a light source and a base member from being transmitted to the base member and adversely affecting it.
The present invention provides an optical unit that splits light emitted from a light source 1 into a plurality of colors and guides the light to a light modulation element corresponding to each color. A heat diffusing member 101 is attached to a light shielding member 100 that shields part of the emitted light. The light shielding member 100 is made of, for example, a metal plate or a resin plate, and the thermal diffusion member 101 is a thin film member having high thermal diffusion performance such as a graphite member (for example, a graphite sheet).
[Selection] Figure 1

Description

  The present invention relates to an optical unit and a display device that split light emitted from a light source into a plurality of colors and guide the light to a light modulation element corresponding to each color.

  Projection-type display devices such as liquid crystal projectors split light emitted from a light source into three primary colors of R (red), G (green), and B (blue), and each color modulation element (corresponding to a predetermined path) Liquid crystal panel or the like), modulation is performed by a combining prism, and then the image is enlarged and projected on a screen via a projection optical system (for example, see Patent Document 1).

JP 10-133303 A

  Here, the optical unit that divides the light emitted from the light source into a plurality of colors and guides the light to the light modulation element corresponding to each color, an optical integrator (fly eye lens) that condenses the light from the light source or PS conversion An element is provided, and a base member for supporting these optical components is provided. Since the base member is a resin part, a light shielding plate made of a thin metal plate is attached from the viewpoint of preventing direct light from a light source.

  However, when the light from the light source hits the light shielding plate of the metal thin plate, a heat spot is generated, and the temperature of the base member rises through the light shielding plate, thereby deteriorating the dimensional accuracy of the base member that is a resin part. The problem arises.

  The present invention has been made to solve such problems. That is, the present invention is an optical unit that splits light emitted from a light source into a plurality of colors and guides the light to a light modulation element corresponding to each color. A heat diffusing member is attached to a light shielding member that shields the part.

  Here, the light shielding member is made of, for example, a metal plate or a resin plate, and the heat diffusion member is a thin film member having high thermal diffusion performance such as a graphite member (for example, a graphite sheet).

  Thereby, even if the light from the light source is irradiated to the light shielding member, heat can be diffused by the heat diffusing member, and it is not necessary to generate a heat spot on the light shielding member.

  Further, the light shielding member is disposed at the light source attachment port of the base member that supports the lens that collects the light emitted from the light source, and the heat diffusion member is attached to the surface of the light shielding member opposite to the light source. It is what. For this reason, even if it is a base member near a light source, it becomes possible to prevent that the influence of the heat by the light irradiated from a light source is transmitted directly.

  The present invention also includes a light source, an optical unit that splits light emitted from the light source into a plurality of colors, guides the light to a light modulation element corresponding to each color, and synthesizes the light modulated by each light modulation element. And a projection optical system that projects the light synthesized by the optical unit. The optical unit includes a light shielding member that is provided at a light source mounting portion and shields part of the light emitted from the light source. In addition, a heat diffusing member is attached to the light shielding member.

  According to the present invention, heat can be diffused by the heat diffusing member even when the light shielding member is irradiated with light from the light source, and it is not necessary to generate a heat spot on the light shielding member.

  The present invention has the following effects. That is, it is possible to eliminate the concentration of heat due to the light radiated from the light source to the light shielding member, and it is possible to display a high-quality image by suppressing the dimensional accuracy error due to heat.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Overall configuration of optical unit)
FIG. 1 is a schematic exploded perspective view illustrating the overall configuration of the optical unit according to the present embodiment. The optical unit splits light emitted from the light source 1 into a plurality of colors (R (red), G (green), and B (blue)), and a light modulation element (for example, a liquid crystal panel) corresponding to each color. This is a member assembled by placing optical modulation elements such as various lenses, various mirrors, and a liquid crystal panel at predetermined positions on the casing and optically positioning them.

  Around the optical unit, a light source 1 is provided on the light incident side, a projection lens 13 is provided on the light emission side, a fan 14 for cooling the inside of the unit, and a case upper part 15 serving as a lid for the case of the optical component are also attached. .

  The base member 200 to which the light source 1 is attached supports the optical integrator 2 and the PS conversion element 3 and is made of resin (for example, PC (PolyCarbonate), PPE (PolyPhenylene Ether), PPS (PolyPhenylene Sulfide), BMC (Bulk Molding). Compounds)).

  A predetermined groove is formed in the base member 200, and a fly-eye lens or a PS conversion element 3 constituting the optical integrator 2 is attached to the groove so that optical alignment and support can be performed. It has become.

  A mounting hole for the light source 1 is provided on the front surface of the base member 200. The light source 1 is constituted by a holder incorporating a lamp, and the light source 1 can be set by attaching the holder to the base member 200.

  When the light source 1 is attached to the base member 200, the light shielding member 100 is interposed between the base member 200 and the light source 1 in order to prevent light emitted from the light source 1 from directly hitting the base member 200.

  In the present embodiment, a heat diffusing member is attached to the light shielding member 100 so that even if the light irradiated from the light source 1 hits the light shielding member 100, the heat generated by the light is diffused so as not to generate a heat spot. Yes.

  In the optical unit, in addition to the optical integrator 2 and the PS conversion element 3, a condenser lens, a mirror for spectroscopic and reflection, a light modulation element corresponding to each color, and light (video light) of each color after light modulation. A cross prism to be combined is disposed, and a projection lens 13 is attached to the light emitting side.

(Configuration example of optical unit)
FIG. 2 is a schematic diagram illustrating a configuration example of an optical unit of a three-plate liquid crystal projector. That is, the optical unit includes an optical integrator 2, a PS conversion element 3, the optical device of the present embodiment (dichroic mirrors 4, 5, mirrors 6, 7, 8, condenser lenses L12, L14, L16, relay lenses L13, L15, and trimming. Filters F1 to F3, etc.), LCDs (liquid crystal panels) 9 to 11 as light modulation elements, and a cross prism 12 are incorporated in one package, and the alignment of various optical components is completed.

  Therefore, when configuring a three-plate liquid crystal projector, a display device can be easily constructed by attaching the light source 1 and the projection lens 13 to this unit. For example, the optical axis between the unit and the projection lens 13 is set simply by attaching this unit to the housing H to which the projection lens 13 is attached, and the light source 1 is arranged in an apparatus housing (not shown) to thereby form a three-plate liquid crystal. A projector can be configured.

  In this optical unit, the light emitted from the light source 1 is sent to the dichroic mirror 4 via the optical integrator 2, the PS conversion element 3, and the condenser lens L11, and for example, only B (blue) is reflected, and R (red) and G (green) is transmitted.

  The B (blue) color light reflected by the dichroic mirror 4 is reflected by the mirror 6 and sent to the LCD 9 via the condenser lens L14, and is modulated into an image corresponding to blue. On the other hand, R (red) and G (green) light transmitted through the dichroic mirror 4 is sent to the dichroic mirror 5, where only R (red) is reflected and G (green) is transmitted.

  The R (red) color light reflected by the dichroic mirror 5 is sent to the LCD 10 through the condenser lens L12 and modulated into an image corresponding to red. On the other hand, the G (green) color light transmitted through the dichroic mirror 5 is reflected by the mirror 7 via the relay lens L13 and reflected by the mirror 8 via the relay lens L15. Then, it is sent to the LCD 11 through the condenser lens L16 and modulated into an image corresponding to green.

  The lights modulated by the LCDs 9, 10, 11 are combined by the cross prism 12 and enlarged and projected onto the screen S via the projection lens 13.

(Configuration of light shielding member)
FIG. 3 is a schematic diagram illustrating the configuration of the light shielding member. As described above, the light shielding member 100 is disposed between the base member 200 and the light source 1 and shields unnecessary portions so that light emitted from the light source 1 does not directly hit the base member 200. Therefore, a hole 100a for transmitting light is provided in the center of the light shielding member 100, and a light shielding portion is formed around the hole 100a.

  In the light shielding member 100 of the present embodiment, the heat diffusion member 101 is provided on the surface (back surface) opposite to the surface (front surface) to which the light source is attached. Thereby, the direct contact with the light shielding member 100 and the base member 200 (refer FIG. 1) can be avoided.

  As the thermal diffusion member 101, a thin film material having high thermal diffusion performance is applied, and for example, a graphite (graphite) member, preferably a graphite sheet is used. The heat diffusing member 101 may be made of a material having a higher thermal conductivity coefficient than that of the light shielding member 100 other than the graphite member, and may be a metal or resin other than graphite.

  When a graphite sheet is used as the heat diffusion member 101, the thickness of the graphite sheet is about 0.1 mm. The graphite sheet is attached to a necessary portion of the light shielding member 100 via, for example, a silicone adhesive.

  The light shielding member 100 is provided by, for example, pressing a thin metal plate, and stainless steel is used as the thin metal plate, for example. The light shielding member 100 may be configured as a resin molded product. When the resin is used, predetermined heat resistance, linear expansion coefficient, dimensional accuracy / stability, and workability are required. Examples of applicable resins include BMC (Bulk Molding Compounds), PPS (PolyPhenylene Sulfide), PC (PolyCarbonate), and PPE (PolyPhenylene Ether).

  Here, BMC and PPS are excellent in workability because the deflection temperature under load (1.82 MPa) which is one of heat resistance is excellent at BMC 230 ° C. and PPS 260 ° C. In particular, BMC is excellent in dimensional accuracy and stability.

  On the other hand, although PC and PPE are inexpensive, they are inferior to BMC and PPS in heat resistance, dimensional accuracy and stability.

  In the present embodiment, even when a resin is used as the light shielding member 100, the heat diffusion member 101 is attached. Therefore, not only BMC and PPS having excellent characteristics as described above, but also PC or PPE is sufficient. It becomes possible to apply to.

  FIG. 3B shows the state of thermal diffusion by the thermal diffusion member 101 with arrows. The light shielding member 100 is irradiated with light from the light source at a position indicated by a broken line ◯ in the figure, and is sent through the hole 100a to the inside of the optical unit. At this time, the light from the light source is irradiated to a part of the light shielding portion around the hole 100a, which becomes a heating region. By attaching the heat diffusing member 101, the heat generated in this heating region diffuses outward as indicated by arrows in the figure, and the heating region is locally heated as a heat spot (heating concentration portion). Nothing will happen.

  An edge of the light shielding member 100 is provided with a fold, and the wind from the cooling fan is applied to this portion. Therefore, the heat diffused outward is dissipated to the outside from the folded edge of the light shielding member 100.

(Overall configuration of display device)
FIG. 4 is a diagram illustrating an example of an optical configuration of a projection display device (three-plate liquid crystal projector) to which the optical unit of the present embodiment is applied. In FIG. 4, the three-plate liquid crystal projector includes a light source 1, an optical integrator 2, a PS conversion element 3, LCDs 9 to 11, a cross prism 12, and a projection lens 13.

  In this three-plate liquid crystal projector, the light beam emitted from the light source 1 is converted into a parallel light beam by a lens system (not shown), the light beam outside the visible light region is shielded by the UV-IR cut filter, and the light is transmitted through the light shielding member 100. The light enters the optical integrator 2. The optical integrator 2 forms a multiple light source composed of a plurality of light source images based on the light flux from the light source 1.

  The light beams from the multiple light sources formed by the optical integrator 2 are set in the polarization direction by the PS conversion element 3 and then enter the optical unit of the present embodiment through the condenser lens L11.

  In this embodiment, since the heat diffusing member 101 is attached to the light shielding member 100 described above, the light irradiated from the light source 1 supports the optical integrator 2, the PS conversion element 3, and the condenser lens L11. The heat is not irradiated directly on the light-shielding member 100, and the heat due to the light irradiated on the light shielding member 100 is diffused by the heat diffusion member 101 so that a heat spot is not generated. As a result, the base member 200 is not damaged by heat, and the optical characteristics of the optical integrator 2, the PS conversion element 3, and the condenser lens L11 supported by the base member 200 are not adversely affected, and a high-quality image is obtained. Can be provided.

(Implementation effect)
According to the present embodiment, even when the light source 1 composed of a high wattage lamp is used, it is possible to use an inexpensive material such as a thermoplastic resin as the material of the base member 200, thereby realizing a cost reduction and a high brightness set. It becomes.

It is a typical exploded perspective view explaining the whole optical unit composition concerning this embodiment. It is a schematic diagram which shows the structural example of the optical unit of a 3 plate-type liquid crystal projector. It is a schematic diagram explaining the structure of a light shielding member. It is a figure which shows an example of the optical structure of the projection type display apparatus (3 plate-type liquid crystal projector) to which the optical unit of this embodiment is applied.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Light source, 2 ... Optical integrator 2 ... PS conversion element, 4 ... Dichroic mirror, 5 ... Dichroic mirror, 6 ... Mirror, 7 ... Mirror, 8 ... Mirror, 9 ... LCD, 10 ... LCD, 11 ... LCD, 12 ... Cross prism, 13 ... projection lens, 100 ... light shielding member, 101 ... heat diffusion member, 200 ... base member, F1 ... trimming filter, F2 ... trimming filter, F3 ... trimming filter, L11 ... condenser lens, L12 ... condenser lens, L13 ... Relay lens, L14 ... Condenser lens, L15 ... Relay lens, L16 ... Condenser lens, S ... Screen

Claims (6)

In an optical unit that splits light emitted from a light source into a plurality of colors and guides the light to a light modulation element corresponding to each color.
An optical unit, wherein a heat diffusing member is attached to a light shielding member that is provided at an attachment portion of the light source and shields a part of light emitted from the light source. The optical unit according to claim 1, wherein the light shielding member is a metal plate, and the heat diffusion member is a graphite member. The optical unit according to claim 1, wherein the light shielding member is a resin plate, and the heat diffusion member is a graphite member. 2. The optical unit according to claim 1, wherein the light shielding member is disposed at an attachment port of the light source in a base member that supports a lens that collects light emitted from the light source. The optical unit according to claim 1, wherein the heat diffusing member is attached to a surface of the light shielding member opposite to the light source. A light source;
An optical unit that divides the light emitted from the light source into a plurality of colors, guides the light to a light modulation element corresponding to each color, and synthesizes the light modulated by each light modulation element;
In a display device comprising a projection optical system for projecting light synthesized by the optical unit,
The optical unit is
A display device, comprising: a light shielding member that is provided at an attachment portion of the light source and shields a part of light emitted from the light source; and a heat diffusion member is attached to the light shielding member.