KR20040079334A - Projection System with separate 3 channel color bean transmission mode and projection lens using there - Google Patents

Abstract

PURPOSE: A projection system is provided which has three independent color transparent channels to align a light incident to a LCD imager easily, and a projection lens is provided which is used in the projection system. CONSTITUTION: A lamp(100) radiates a light beam. Two dichroic mirrors(130,135) and a reflector mirror(140) receive the light beam from the lamp and separate it into independent R,G,B color beam. Three light beam transparent channels penetrates the independent R,G,B beam separated by the dichroic mirrors and the reflector. Each beam transparent channel includes condenser lenses(150,153,156) condensing the beam separated from the dichroic mirrors or the reflector mirror, and a LCD imager acting as a switch as to the light beam penetrating the integrator lens, and a projection lens projecting the light beam on a screen.

Description

Projection system with separate 3 channel color bean transmission mode and projection lens using there}

The present invention is a projection system having three independent color transmission channels and a projection lens used therein. In more detail, three independent lenses are used so that light of red (R) green (G) wave (B) The present invention relates to a projection system having three independent color transmission channels which are converged on one screen by passing through two independent color channel transmission mode LCD imagers and a projection lens used therein.

The liquid crystal projector separates the light from the light source for each of R, G, and B through a dichroic mirror, and then provides image information through the liquid crystal to selectively turn on / off the light separated by each color. Device. A liquid crystal projector is an optical system, and a liquid crystal switch that selectively transmits light and an integrator composed of a fly-eye lens or a lens plate, which is a uniform illumination optical element that uniformly illuminates light emitted from a light source. Use the device. Since the liquid crystal is a device having a selective transmission function depending on whether an electric field is applied using polarized incident light on the upper and lower plates, the polarized light should be incident on the liquid crystal. Therefore, only the light source polarized in a predetermined direction through the polarizer reaches the liquid crystal before the light emitted from the light source enters the liquid crystal.

1 is a block diagram of a conventional liquid crystal projection system. At least one lamp 10 is used as the light source as shown in FIG. The light generated by the lamp 10 is reflected in one direction by the reflector 20. The light reflected through the reflector 20 is incident on the first FEL (Fly Eye Lens) lens 31 to adjust the illumination area to the size of the LCD panel 80 and to uniform the light intensity. In this case, the FEL lens 31 is configured to form a single lens by combining lenses of a small cell unit in order to realize maximum uniformity using ambient light. The light corrected by the first FEL lens 31 is once again corrected by the second FEL lens 33 and incident on the polarizing beam splitter (PBS) 35 to P-polarized light and S-polarized light. It is separated and passes only S-polarized light. The PBS 35 is provided with a PBS plate or a PBS thin film obliquely inside. The light polarized by the PBS 35 is focused by a condensing lens 37. The light focused by the condensing lens 37 is reflected by the total reflection mirror 40a and passes through the condensing lens 50 in which the linearity of the light is corrected. The light passes only the red color from the color filter 60a that passes light of a certain color and reflects all other light, and reaches the LCD panel 80a through the total reflection mirror 40b and the R field lens 70a. The LCD panel 80a to which the red light is incident is activated to generate an image corresponding to the red color. Light of a predetermined color that has passed through the color filter 60 is once again filtered by the dichroic lens 70. In addition, the light from which the red color is removed from the color filter 60a passes through the blue light and the green light is reflected by the next color filter 60b, and the green light passes through the G-field lens 70b. 80b), the LCD panel 80b to which the green light is incident is activated to generate an image corresponding to green. The blue light passing through the color filter 60a reaches the LCD panel 80c through the total reflection mirrors 40c and 40d and the B field lens 70c, and is activated by the LCD panel 80c. An image corresponding to blue color is generated.

In this way, the red, green, and blue images generated by the three LCD panels 80 are combined by the synthesis prism 90 to be converted into a complete image, and the combined images are screened through the projection lens unit 95. It is embodied as an enlarged image to provide a clear and lively large screen image to users.

Here, the composite prism 90 serves to combine the images of each color passing through the R, G, and B LCD panels into one, and the projection lens 95 combines the image synthesized through the composite prism 90. It serves to enlarge the projection on the screen.

However, in the optical system of the conventional projector having the above configuration, in particular, a separate light generated by the lamp 10 is reflected by the reflector 20 and corrected by the first FEL lens 31, and the second FEL lens ( 33), after being polarized through the PBS 35, focused by the condensing lens 37 and incident on the total reflection mirror 40a, the first FEL lens 31 and the second FEL lens 33 The alignment must match exactly. That is, if the alignment of the cells of the first FEL lens 31 and the cells of the second FEL lens 33 does not coincide exactly, a problem of light uniformity may occur. Polarization is not properly performed, there is a problem that a phenomenon such as color fall out occurs. In addition, in such a configuration, since it is very difficult to adjust the alignment state of the first FEL lens 31 and the second FEL lens 33, there is an inherent factor that a defect may appear on the screen at all times. If there is a problem that has a great impact on the quality of the product.

In addition, the conventional optical system of the projector requires a synthesis prism 90 for combining images of R, G, and B colors as a component, resulting in an increase in production cost.

The present invention has been made to solve the above-mentioned problems of the present invention, and an object of the present invention is to provide a projection system in which three projection lenses are independently installed.

It is still another object of the present invention to provide a liquid crystal projection system that is easy to align light incident on the LCD imager by using a light collector in the immediately preceding stage of the LCD imager.

It is also an object of the present invention to provide a projection lens for use in a projection system.

In order to achieve the above object, a projection system in which three projection lenses are independently installed, the projection system comprises: a lamp for emitting a beam of light; Dichroic mirrors that receive beams of light emitted from the lamps and separately separate colors into colors of R, G, and B; And three beam transmitting channels through which beams of color separated into R, G, and B are independently transmitted by the dichroic mirrors, wherein each beam transmission channel is formed from the dichroic mirror. A condenser lens that collects the separated beams and an LCD imager that acts as a TN for the beam of light passing through the condenser lens and a projection lens for projecting a beam of light through the LCD imager onto the screen; In front of the lamp, the light emitted from the lamp is reflected at a predetermined angle to direct the dichroic mirrors, and a pair of cold mirrors are provided, and each of the condenser beam channels and the LCD beam is independently provided. Between them, a light collector is installed, and the light collector is either a mirror tunnel light collector or a glass rod light collector, and a light polarizer is coupled to a light exiting part of the light collector. Has a cylindrical or tapered shape with a constant diameter, the polarizer is a wire grid polarizer, and the adhesive tape is attached to the edge of the light exit portion of the beam of light of the light collector, so that the polarizer is connected to the light exit portion of the light collector. And a metal clip inserted into the beam input part and the light exit part of the light collector of the light collector to support the input and output end of the light collector, and a sapphire substrate and an analyzer are coupled to the light exit surface of each LCD imager in order. To reduce the operating temperature of the analyzer and to act as an analyzer by combining a polarizing material to the beam incident surface of the light of each projection lens, and coated on the light incident end of one or more LCD imagers of the three LCD imagers. Using a dichroic filter as anti-dust glass, a cleanup filter or UV filter is installed.

In order to achieve the above another object, the projection lens according to the present invention, the first lens 400 and the crown glass provided with a positive biconvex aspherical lens (positive) The second and third lenses (401 and 402, respectively) and the fourth lens including the convex lens, which constitute the convex lens and the concave lens, which are composed of flint glass, constitute a group of double color lenses. 403); And a fifth lens 404 provided as a convex lens and a sixth lens 405 provided as a concave aspheric lens.

DETAILED DESCRIPTION OF THE INVENTION The detailed description, features, preferred embodiments, and the like of the present invention are described in detail below with reference to the accompanying drawings.

1 is a block diagram of a conventional liquid crystal projection system.

Figure 2 shows the construction of an optical engine of a projection system with three independent color transmission channels according to the invention.

3 is a perspective view showing a state in which the light incident end of the light collector according to the present invention is fixed using a metal clip.

4 is a view showing that the collector rod or the collector tunnel according to the present invention is mechanically supported.

5 is a plan view of a projection lens according to the present invention.

** Explanation of symbols for main parts of drawings **

100: lamp 110, 115: UV filter

130, 135: dichroic mirror 140: reflector

150, 153, 156: condenser lens 160, 163, 166: condenser

170, 173, 176: polarizers 190, 193, 196: LCD imager

200, 203, 206: analyzer 210, 213, 216: projection lens

Figure 2 shows the construction of an optical engine of a projection system with three independent color transmission channels according to the invention.

As shown in FIG. 2, the projection system of the present invention has a parabolic reflector and includes a lamp 100 which is a light source that emits a beam of light close to paraxial, and is provided in front of the lamp 100. First UV filter 110 and second UV filter 115, through the first and second cold mirrors 120, 125, the second UV filter installed to reflect the light passing through the first UV filter 110, Dichroic mirrors 130 and 135 and reflectors 140 installed for color separation of a beam of light. The emitted light is separated into three independent colors of light of R, G, and B, respectively, by the dichroic mirrors 130 and 135 and the reflector 140, and beams of light separated by R, G, and B, respectively. Through these three independent channels, they are combined into a single light to form an image on the screen.

Each of the three independent channels may include three condenser lenses 150, 153, and 156 respectively disposed in front of the dichroic mirrors 130 and 135 and the reflector 140, and the condenser lenses 150 and 153, respectively. 156, three independent light collectors 160, 163 and 166 installed in front of each other, polarizers 170, 173 and 176 installed in the light exit portions of the respective light collectors 160, 163 and 166 and the respective polarizers Each color clean-up filter 180, 183, 186 installed in front of the 170, 173, 176, and each LCD imager 190, 193, 196, and an analyzer serving as a second polarizer. ), 200, 203, and 206 are positioned, and finally, each of the projection lenses 210, 213, and 216 is provided.

When explaining the components of the present invention in detail,

The beam of light emitted from the lamp 100 of the present invention passes through the first UV filter 110 and is reflected by the first cold mirror 120. Then, it is reflected back by the second cold mirror 125 and passes through the second UV filter 115. The beam of light passing through the second UV filter 115 is directed to the dichroic color separation ratters 130 and 135 as a steel plane beam.

In the present invention, a cold mirror is a bulb equipped with a conventional reflector, and a glass gas is provided behind the bulb to form a visible light reflecting infrared transmission interference filter film on the inner surface thereof to reflect visible light forward of the light reflected from the light bulb and to emit infrared light. It is known to transmit visible light with less infrared rays by transmitting to the rear side, and such a reflector is referred to.

The role of the cold mirrors 120 and 125 and the UV filters 110 and 115 of the present invention is to remove infrared radiation (heat) and ultraviolet radiation from the beam of the light source, which is the three through which the beam of light passes. This is because the components of the independent channel portion, in particular, have an adverse effect on the life of the LCD imagers 190, 193, 196. In the present invention, one of the two cold mirrors 120 and 125 may be replaced with a common flat mirror, and one or both of the UV filters 110 and 115 may be removed if not needed.

In the dichroic mirrors 130 and 135 and the reflector 140 provided for color separation of the beam of light passing through the second UV filter 115 of the present invention, the red light R is a red dichroic mirror. The green light (G) of the transmitted cyan light is directed into the red channel by 130, and is reflected into the green channel by the yellow dichroic mirror 135, and the remaining transmitted blue light ( B) is reflected into the blue channel by the reflector 140.

Each collector 160, 163, 166 installed in each of the three color channels of the present invention is a glass rod collector, or a mirror tunnel collector. These collectors employ polarization recovery. In the present invention, the light collectors 160, 163, and 166 have a light incident side on which light emitted from a light source is incident and a light exit side on which light is emitted, and serve to uniformly emit light incident on the light incident side. In particular, the rod concentrator forms a plurality of virtual light-source points, and each virtual light source point radiates most of the incident light flow to the light exiting side. As the rod concentrator increases in length, the virtual light source point increases, thereby improving uniformity of emitted light. Meanwhile, the light collectors 160, 163, and 166 may be formed to taper in the lateral direction. In the embodiment of the present invention, a rod collector is used.

Light emitted from the light exit portions of the light collectors 160, 163, and 166 of the present invention passes through the polarizers 170, 173, and 176. In an embodiment of the present invention, the polarizers 170, 173, 176 are bonded Moxtek type polarizers bonded in optical grade to the surface of the light exit portions of the light collectors 160, 163, 166. . Color based polarizers can be used.

In the present invention, the beam of light emitted from the polarizers 170, 173, 176 passes through the color clean-up filters 180, 183, 186. Within the red and green channels, cleanup filters 180, 183 are used to provide color purification, and within the blue channel, an additional UV filter is applied to the blue channel's LCD imager 196 from the UV radiation. It is used to protect more.

In another embodiment of the present invention, three clean-up filters 180, 183, 186 are provided as cover glass (or dust free glass) on the LCD imager 190, 193, 196. By using it can be removed as a component.

The LCD imagers 190, 193, 196 of the present invention serve as a general transmitted TN device, rotating the polarization indicator of the transmitted light when no power is supplied and not rotating when the power is completely supplied. Instead, it provides various intermediate states of elliptical polarization in the intermediate states.

An analyzer (200, 203, 206), which is the second polarizer of the present invention, is mounted on a sapphire substrate thermally coupled to the cell carrier. This is to remove heat generated in the analyzer by absorbing the light, thereby extending the life of the analyzer. In addition, the analyzer 200, 203, 206 can also be mounted on glass.

An image in which three images on the screen-red, green and blue-are merged on the screen by the projection lenses 210, 213, 216 of the present invention is used to determine the position of the projection lenses 210, 213, 216. By changing to form a single combined color image. In the present invention, the projection lenses 210 and 216 of the red and blue channel are slightly tilted toward the center so that the red and blue images merge with the green central image.

3 is a perspective view showing a state in which the light incident end of the light collector according to the present invention is fixed using a metal clip. Referring to FIG. 3, the light incidence ends of the light collectors 160, 163, and 166 are fitted to the metal clips 300 to be fixed.

4 is a view showing that the collector rod or the collector tunnel according to the present invention is mechanically supported.

As shown in FIG. 4, for example, the light collector 160 installed in the red light channel, which is one of the light collectors according to the present invention, includes a polarizer 170 and a clean-up filter 180 on the light-outing side of the integrator 160. Are attached sequentially. The polarizer 170 is attached to the light collector 160 using an adhesive tape 161. Arrows indicate the direction of light travel. In the present invention, the polarizer 170 is a Moxtek polarizer.

The adhesive tape 161 is for attaching the polarizer 170 to the light collector 160, and it is preferable to use a silicone tape.

The inexpensive wire grid polarizer 170 has a substrate, and the elongated composite wires are arranged in parallel in a grid or array form on the first side of the substrate so that the projected light is polarized by the composite wires. At this time, each wire adjacent to each other has a grid period shorter than the propagation length of the incident light. Each wire also has an internal structure in which elongated metal wires and a dielectric layer are alternately arranged. In the embodiment shown in FIG. 4, the wire grid polarizer 170 is attached in a direction in which the first surface of the substrate on which the wire is disposed is opposite to the light exit side of the light collector 160, wherein the adhesive tape 161 is formed of at least a wire. It should be attached to the rim of the first side of the substrate that is not disposed.

The cleanup filter 180 may use a dye-based polymer clean-up polarizer as a polarizer having a relatively low polarization but a high transmittance. It is demonstrated that the cleanup filter 180 may be used in combination with a polarizer having a relatively high degree of polarization, that is, a good polarization effect by using the wire grid polarizer 170. In this case, the wire grid polarizer 170 and the cleanup filter 180 are preferably bonded using an adhesive having an appropriate refractive index to avoid light loss on the surface.

Meanwhile, a glass plate may be attached to the rear end of the cleanup filter 180 based on the traveling direction of light.

5 shows a configuration of a projection lens of an embodiment according to the present invention. The lens numbers were set in the order of installation from the light incident side to the light exit side. Therefore, in FIG. 5, the right lens is the first lens, and the leftmost lens is the sixth lens. The projection lens according to the present invention is a convex lens and a flint glass composed of a first glass 400 and a crown glass, which are provided with a positive biconvex aspheric lens and a crown glass. The second and third lenses (401 and 402, respectively) and the fifth lens (5) provided with convex lenses and the second and third lenses (401 and 402, respectively) constituting the chrominance dual lens in one group. 404 and a sixth lens 405 provided with a concave aspherical lens. The material of the lens may be the second, third, fourth and fifth lenses 401, 402, 403, 404 may be made of glass and the remaining lenses 400, 405 may be made of plastic, in particular the second and third lenses. Only 401, 402 may be made of glass and the remaining lenses 400, 403, 404, 405 may be made of plastic. The second and third lenses 401, 402 may also be made of glass, the remainders 400, 403, 404, 405 may be made of plastic, and the fourth and fifth lenses 403, 404 may also be aspherical. In addition, it is possible to adjust the distance between the fourth and fifth lenses 403, 404 for the magnification function, in which case each projection lens 210, 213, 216 of R, G, B tricolor ) Are all adjustable.

The following lens data is for a projection lens (f = 14.4mm, f / # 2.9) of a 36-inch real projection TV.

GENERAL LENS DATA:

Field: 5

Vignetting Factors

Wavelengths: 3

SURFACE DATA SUMMARY:

SURFACE DATA DETAIL:

EDGE THICKNESS DATA:

MULTI-CONFIGURAION DATA:

INDEX OF REFRACTIN DATA:

THERMAL COEFFICIENT OF EXPANSION DATA:

F / # data:

The F / # calculation takes into account the vignette factor and ignores the surface aperture ratio.

Global Vertex Coordinates, Direction, Orientation, and Rotation / Offset Matrix (GLOBALVERTEX COORDINATES, ORIENTATIONS, AND ROTATION / OFSET MATRICES):

Cardinal Points:

The object space position is measured with respect to surface 1.

Image space position is measured relative to the image surface.

Indexes in both object space and image space are considered.

The projection system having three independent color transmission channels according to the present invention is an optical engine useful for rear projection television in which the distance between the projection lens and the screen on which the image is projected is fixed. After separating the light beams, the light beams of the separated colors are collected using a light collector, thereby increasing the efficiency of light of the color.

The liquid crystal projection system according to the present invention has an advantage that it is easy to align the light incident on the LCD imager as compared to the liquid crystal projection system that does not use the condenser by using the light collector just before the LCD imager.

In addition, by not installing an expensive color synthesis prism for synthesizing the color light separated into R, G, B installed in the conventional single channel optical lens, there is an effect that can reduce the cost of production.

Claims (10)

A lamp emitting a beam of light; Two dichroic mirrors and reflectors that receive a beam of light emitted from the lamp and separately separate colors into R, G, and B colors; And A beam transmission channel of three light beams each independently transmitted by R, G, and B beams separated by the dichroic mirrors and the reflector; Each beam transmission channel, A condenser lens collecting beams separated from the dichroic mirror or reflector; An LCD imager that serves as a switch for the beam of light passing through the condenser lens; And And a projection lens for projecting a beam of light passing through the LCD imager onto a screen. The method of claim 1, Three independent mirrors, which are installed between the lamp and the dichroic mirror, have a pair of cold mirrors at an angle to reflect the beam of light emitted from the lamp to the dichroic mirrors. Projection system with color transmission channels. The method of claim 1, And each condenser beam channel is independently provided with a condenser between the condenser lens and the LCD imager. The method of claim 3, wherein The condenser is either a mirror tunnel condenser or a glass rod condenser, Polarizers are coupled to the light exit portion of the light collector, The shape of the light collector has a cylindrical or tapered shape having a constant diameter, And the polarizer is a wiregrid polarizer. The method of claim 4, wherein And an adhesive tape attached to an edge of the light exit portion of the beam of light of the light collector so that the polarizer is attached to the light exit portion of the light collector. The method of claim 3, wherein A projection system having three independent color transmission channels, characterized in that a metal clip is fitted to the beam input and output parts of the light of the collector to support the input and output end of the collector. The method of claim 1, And a sapphire substrate and an analyzer are installed on the light emitting surface of each LCD imager in order to reduce heat generated from the analyzer. The method of claim 1, And a polarizing material coupled to the beam incident surface of light of each projection lens to act as an analyzer. The method of claim 1, And a dichroic filter coated as an anti-dust cover on the light input of one or more of the three LCD imagers. A first lens 400 provided as a positive biconvex aspherical lens; Second and third lenses (401 and 402, respectively) in which a convex lens made of crown glass and a concave lens made of flint glass are combined to form a sagittal double lens in one group; A fourth lens 403 provided as a convex lens; A fifth lens 404 provided as a convex lens; And And a sixth lens (405) provided as a concave aspherical lens.