CN1208679C - Heat sink for light pipes - Google Patents

Abstract

The invention provides a heat sink of a light pipe, which is arranged on an optical engine of a projector and optically coupled with a light source. The heat dissipating device includes: a cladding body made of heat conductive material, the cladding body is cladded on the light pipe, so that the heat energy generated by the light source can be uniformly distributed on the light pipe; and a fan for reducing the heat energy spread on the light pipe.

Description

Heat sink for light pipes

                      

The invention relates to a heat dissipation device for a light guide, in particular to a heat dissipation device for a light guide used in a DLP (Digital Light Processing) projector.

Background technique

Early projection technology was projected by three guns of cathode ray tube (Cathode Ray Tube, CRT), but because of the large volume and poor resolution of the projector required for the application of this technology, it was later adopted by liquid crystal display (Liquid Crystal Display, LCD) replaced by projection technology.

The projection principle of LCD projection technology is to project light through the red, green and blue three primary color filters, guide the three primary colors through three LCD panels (LCD Panel), and then synthesize the projection image. Generally speaking, the color saturation and color temperature of LCD projection technology are better, but the transmissive LCD panel is limited by the light transmittance, so the light efficiency will be worse than the reflective one, and it is also limited by the optical engine ( Optical Engine) structure, the volume cannot be made small, and the weight is relatively heavy.

In recent years, there has been a new projection technology, Digital Light Processing (DLP) technology, please refer to US Patent No. US 5,658,063. This DLP projection technology was successfully developed in 1996 by Texas Instruments Incorporated in Dallas, Texas. Different from the way in which LCD projection technology passes light through the liquid crystal panel for imaging in the past, the principle of DLP projection is to project light through a high-speed rotating red, green and blue three-color turntable and then project it to the DLP chip for reflection imaging. The key component of this technology is a semiconductor reference component controlled by two-bit (bit) pulse modulation, that is, a digital micromirror device (Digital Micromirror Device, DMD). Acquired from Instrument Company.

This DMD chip is a fast and reflective digital optical switch that can control the light source very accurately. Since the DLP projection technology changes the light to be reflected by the micro-mirrors on the DMD chip to generate images, this technology can greatly reduce the weight and volume of the projector, and at the same time provide better light efficiency and higher resolution. DLP projection technology is very suitable for applications that require high brightness and high resolution due to the reflective and high fill rate characteristics of DMD, which can produce high optical efficiency. The better heat dissipation of DLP projection technology also allows DLP projectors to use high-wattage light sources without reducing the life of DMD. At the same time, the fully digital design of DLP projection technology provides more accurate and stable reproduced images.

In a DLP projector using DLP projection technology, the light pipe (Light Pipe) installed between the light source and the optical engine is an indispensable refraction component in the optical components. Generally speaking, the light pipe is formed by bonding and laminating four pieces of glass, and the clamping device (Clip Means) and the bracket (Bracket) are used as the positioning device of the light pipe, and the screws are used to move up and down and left and right. Adjustment.

Please refer to FIG. 1a and FIG. 1b . FIG. 1a and FIG. 1b show a prior art configuration view of a light pipe disposed on an optical engine. As shown in FIG. 1a, in the prior art, the light guide 13 is supported on the plane 121 of the magnesium-aluminum alloy optical engine 12 by using the rigid elastic force of the clamping device 11, and the light guide 13 is positioned so that the light guide 13 and the light source ( not shown) optically coupled for delivery to refract light. Moreover, in the prior art, the light guide 13 is fine-tuned left and right by screws 14 , and the light guide 13 is fine-tuned up and down by screws 15 . As shown in FIG. 1 b , the light pipe 13 in the prior art is generally formed by laminating four pieces of glass 131 , 132 , 133 , and 134 with glue. Under this configuration of the light pipe 13, because the temperature of the light pipe 13 close to the light source is relatively high, if the temperature exceeds the heat-resistant specification temperature of the adhesive, the light pipe 13 will not be able to bear the pressure from the side and the two sides will be damaged. Glasses 131, 133 collapse.

In this regard, if a heat dissipation device can be designed for the light guide 13, the heat energy transmitted from the light source to the light guide 13 can be evenly distributed, or the heat energy dispersed on the light guide 13 can be further reduced, which will effectively reduce the heat energy caused by the glue. influence, and can prevent the collapse of the light guide 13.

Contents of Invention

The purpose of the present invention is to provide a simple heat dissipation device for light pipes, which can not only distribute the heat energy transferred from the light source to the light pipes evenly, but also further reduce the heat energy distributed on the light pipes.

The object of the present invention is achieved by providing a heat dissipation device for a light guide, which is suitable for dissipating heat from a light guide, the light guide is arranged on an optical engine of a projector, the projector has a light source, the light source A light is generated to pass through the light pipe, and the heat dissipation device includes: a covering body (covering), the covering body is made of a heat-conducting material, and the covering body is covered on the light pipe; a clamping device , used to pinch the covering body and the light pipe, so that the light pipe and the covering body are positioned on the optical engine; wherein, when the light passes through the light pipe, a heat energy will be generated, and the covering body is the Thermal energy is evenly distributed to the light pipe.

Another object of the present invention is to provide a heat dissipation device for a light pipe, and the heat dissipation device can reduce the collapse of the light pipe.

In order to achieve this goal, the present invention provides a heat dissipation device for a light guide, which includes a covering body made of a heat-conducting material, through which the covering body is covered on the light guide, so as to uniformly heat the heat energy generated by the light source. spread over the light guide.

Another object of the present invention is to provide a heat dissipation device for a light pipe with materials that are easy to obtain and easy to manufacture, such as using a thin metal sheet with good heat dissipation. Therefore, in a preferred embodiment of the present invention, the wrapping body is made of an aluminum foil sheet.

Another object of the present invention is to provide a heat dissipation device for a light pipe that can effectively reduce heat energy, so as to avoid heat energy from accelerating the collapse of the light pipe. To this end, the present invention further includes a fan positioned on the optical engine to thereby reduce heat energy dissipated on the light pipe.

According to the above features, the light guide of the present invention has a first end and a second end, the first end is close to the light source, the light guide is glued with several pieces of glass, wherein the covering body will The temperature of the first end is lowered so as not to exceed a heat-resistant specification temperature of the adhesive.

Description of drawings

FIG. 1a is a configuration diagram of a prior art light guide and optical engine;

Figure 1b is a schematic diagram of the light guide in Figure 1a;

Fig. 2a is the composite diagram of an embodiment of the application of the present invention;

Figure 2b is an exploded schematic diagram of an embodiment of the application of the present invention;

FIG. 3 is a combined view of a light guide and its covering body according to an embodiment of the present invention.

Specific implementation content

Light pipe (Light Pipe) is an indispensable optical refraction component in DLP projectors. Generally speaking, the light guide is arranged on the reference plane of the optical engine, and is optically coupled with the light source (optical coupling), so that the light from the light source is refracted inside the light guide, and projected through the red, green and blue three-color turntable on the optical engine , and then projected onto the DMD chip for reflection imaging. Based on optical requirements, the light pipe is usually designed as a structure of four pieces of glass bonded with glue. Therefore, once the temperature on the light pipe exceeds the heat-resistant specification temperature of the glue, the light pipe is prone to collapse. Therefore, the present invention additionally proposes a heat dissipation device for the light pipe, which can overcome the disadvantages of the prior art, that is, avoid the optical blue edge phenomenon caused by the collapse of the light pipe.

2a and 2b, the present invention utilizes the clamping device 21, brackets 26, 27 to position the light guide 23 on the plane 221 of the optical engine 22, so that the light guide 23 is optically coupled with the light source (not shown) to For transmission and refraction of light. It should be noted here that the clamping device 21, optical engine 22, light guide 23, brackets 26 and 27 of the present invention are different from the prior art clamping device 11, optical engine 12, light guide 13, bracket 16 and 17 is largely the same. However, the difference is that the present invention further includes a heat dissipation device to reduce the influence of thermal energy on the adhesive, thereby effectively preventing the light pipe 23 from collapsing.

As shown in FIG. 2 a and FIG. 2 b , in an embodiment of the present invention, the clamping device 21 has elastic pieces 211 and 212 , and screws 213 and 214 . The brackets 26 and 27 are adhered to the two ends of the light guide 23 respectively, and the elastic pieces 211 and 212 are in elastic contact with the brackets 26 and 27 respectively, and the screws 213 and 214 can connect the brackets 26 and 27 together with the light guide 23 and the coating. The body 28 is locked on the plane 221 of the optical engine 22 , and the fan 29 is disposed on the plane 221 .

In this way, the light guide 23 can be positioned by the clamping device 21 so that the light guide 23 is optically coupled to the light source (not shown), and the light guide 23 is covered by a cladding 28 made of a heat-conducting material, as shown in FIG. 3, so that the heat energy generated by the light source can be evenly distributed to the light guide 23, so as to prevent the temperature of the part of the light guide 23 close to the light source from being too high.

In a specific embodiment of the present invention, the covering body 28 is made of metal with good thermal conductivity, such as aluminum foil, because aluminum foil has good heat resistance and soft adhesion, and is easy to obtain and process, so it is very suitable. It is used as the material of the covering body 28 of the present invention. Moreover, the thickness of the aluminum foil used in the present invention is only 0.05 mm, so that the precision requirements for the small-sized light guide 23 can be well controlled. Furthermore, the covering body 28 made of aluminum foil can also reduce stray light entering the light pipe 23 .

In addition, in a preferred embodiment of the present invention, the present invention further arranges a fan 29 on the plane 221 of the optical engine 22, and the heat convection effect generated by the fan 29 is used to reduce the heat spread on the light guide 23 and the covering body 28. The thermal energy and further reduce the temperature to prevent the light pipe 23 from collapsing due to the temperature exceeding the heat-resistant specification temperature of the glue.

Through the above-mentioned configuration, the present invention can overcome the disadvantage that the light pipe is easy to collapse in the prior art, and increase the selectivity of the glue for bonding the four pieces of glass of the light pipe. However, although the present invention has been disclosed in conjunction with the above preferred embodiments, the present invention is not limited thereto. Anyone skilled in the art can make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection of the present invention The scope should be defined by the claims.

Claims (5)

1, a kind of heat abstractor of photoconductive tube is applicable to that this photoconductive tube is arranged on the light engine of a projector to photoconductive tube heat radiation, and this projector has a light source, and this light source produces a light by this photoconductive tube, and this heat abstractor comprises:

One cladding (covering), this cladding are made by a Heat Conduction Material, and this cladding is coated on this photoconductive tube;

One clamping device is used for seizing on both sides by the arms this cladding and this photoconductive tube, and this photoconductive tube and this cladding are positioned on this light engine;

Wherein, this light will produce a heat energy during by this photoconductive tube, this cladding be with this heat energy uniformly dispersing to this photoconductive tube.

2, heat abstractor as claimed in claim 1 is characterized in that, this cladding is that a metal is made.

3, heat abstractor as claimed in claim 1 further comprises a thermal convection device (heatconvection means), is disseminated to heat energy on this photoconductive tube for reduction.

4, heat abstractor as claimed in claim 3, wherein this thermal convection device is a fan, this fan is to be positioned on this light engine.

5. heat abstractor as claimed in claim 1, wherein this photoconductive tube has one first end and one second end, this first end is that this photoconductive tube is to bind several pieces glass with a viscose near this light source, and wherein this cladding reduces the temperature of this first end to be no more than a heat-resisting specification temperature of this viscose.

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