KR0137590B1 - Projector using a plurality of prisms - Google Patents

Abstract

The present invention relates to a projection image display device, and more particularly, to a projection image display device using a prism.

SUMMARY OF THE INVENTION An object of the present invention is to provide a projection image display device using a prism that facilitates assembly of an optical system.

It is still another object of the present invention to provide a projection image display apparatus using a prism capable of minimizing a path difference of an entire optical system.

The projection image display device using the prism according to the present invention includes a light source 51 for emitting white light having high brightness, and first, second, third, fourth and fifth prisms 62 which are integrally fixed in contact with each other. 63, 64, 65, 66, field lenses 53, 54, 55 fixed in contact with the second, third and fourth lenses, the optical path controller 52, and the projection lens 97, the first prism 62 has a mirror coating portion 61 for reflecting light emitted from the light source 51, the bonding surface of the second and third prism (63, 64) The first coating part 67 is formed to reflect red light from the white light reflected by the mirror coating part 61 and transmit green and blue light, and the third and fourth prisms 64 and 65 are formed on the first coating part 67. A second coating part 68 is formed on the bonding surface to reflect blue light from green and blue light transmitted from the first coating part 67 and to transmit green light.

Description

Projection Image Display Device Using Prism

1 is a schematic diagram of a conventional projection image display device;

2 is a schematic diagram of a projection image display apparatus using the prism of the present invention;

3 is a view showing a coating portion of the fifth prism.

Explanation of symbols on the main parts of the drawings

50: projection image display device, 52, 53, 54: field lens,

52: optical path controller, 61: mirror coating,

62, 63, 64, 65, 66: prism, 67, 68: the first, second coating,

96: aluminum coating,

The present invention relates to a projection image display device, and more particularly, to a projection image display device using a prism.

An image display apparatus is classified into a direct image display apparatus and a projection image display apparatus according to a display method.

The direct view type image display apparatus includes a CRT (Cathode Ray Tube). The CRT image display apparatus has a good image quality but has a problem such as an increase in weight and thickness as the screen is enlarged, and a high price. There is a limit.

Projection type image display devices include a large crystal display (hereinafter referred to as an LCD), and such a large screen LCD can be thinned to reduce the weight. However, the LCD has a high light loss due to the polarizing plate, and a thin film transistor for driving the LCD is formed for each pixel, so that there is a limit in increasing the aperture ratio (light transmission area).

Accordingly, a projection image display device using Actuated Mirror Arrays (hereinafter referred to as AMA) has been developed by Aura, USA.

The projection image display device is divided into one-dimensional AMA and two-dimensional AMA. The one-dimensional AMA has mirror surfaces arranged in an M × 1 array, and the two-dimensional AMA has mirror surfaces arranged in an M × N array. Therefore, a projection image display device using a 1D AMA pre-scans M x 1 rays using a scanning mirror, and a projection image display device using a 2D AMA projects M x N luminous fluxes to form an array of M x N pixels. Branches represent images.

1 is a schematic diagram of a conventional projection image display apparatus.

This projection image display apparatus 10 includes a light source 11, a field lens 13, an optical separator 15, an optical path controller 18, a light amount controller 41, and a projection lens 47.

The light source 11 emits high brightness white light. Then, the field lens 13 causes the light emitted from the light source 11 and reflected by the light amount controller 41 to form an image on the optical path controller 18 and the aberration of the secondary light beam reflected by the optical path controller 18. To correct the light quantity controller (41).

The optical separator 14 includes first and second dichroic mirrors 15 and 16 to separate the white light passing through the field lens 13 into red, green, and blue, and to adjust the optical path controller 18. Reflects each of the secondary luminous fluxes reflected in the direction opposite to the incident light.

The optical path controller 18 includes mirrors 23, 31 and 39 that reflect incident light on the driving substrates 20, 27 and 35 so that the path of the light is adjusted so as to correspond to the pixels. The first, second and third actuator array panels 19, 25 having M x N mounted actuators 21, 29, 37 which allow the fields 23, 31, 39 to have an inclination. (33). The driver substrates 20, 27, 35 are embedded with M x N transistors (not shown), and the actuators 21, 29, 37 are electrically connected to the transistors. Mounted on (20), (27) and (35), the mirrors (23), (31), (39) mounted on the top are deformed by an electric field generated by an image signal.

The light amount adjuster 41 reflects light incident from the light source 11, and adjusts the amount of light reflected from the mirrors 23, 31 and 39 by the hole 46 and passed through the field lens 13. Pass it through. The light amount controller 41 has a predetermined angle, for example, about 30 degrees with the light source 11.

The projection lens 47 projects the light whose light amount is adjusted by the light amount adjuster 41 onto the screen 49 to display a desired image.

However, in assembling the optical system of the projection image display device as described above, the first and second color-dividing mirrors generally have to be assembled with a precision of about 0.01 °. There was a difficult assembly problem.

Accordingly, it is an object of the present invention to provide a projection image display device using a prism that facilitates assembly of an optical system.

Still another object of the present invention is to provide a projection image display apparatus using a prism capable of minimizing the path difference of the whole optical system.

Projection type image display apparatus using the prism of the present invention for achieving the above object is a light source for emitting white light of high brightness, the first, second, third, fourth and fifth prism integrated together; Among the white light reflected from the first prism, the first and second coating parts reflecting red and blue light and transmitting the remaining light, and the red, blue and green light reflected or transmitted from the first and second coating parts. An optical path adjuster for reflecting the color of the light by adjusting the optical path for each pixel; A field lens bonded to the second, third and fourth prisms and adjacent to the optical path controller to form reflected light without loss in the fifth prism, and color light passing through the fifth prism. It consists of a projection lens for projecting the surface.

Hereinafter, with reference to the accompanying drawings will be described in detail the present invention.

2 is a plan view schematically showing a projection image display device 50 using a prism according to an embodiment of the present invention.

The projection image display device 50 using the prism includes a light source 51 and first, second, third, fourth and fifth prisms 62, 63, 64 and 65 which are integrally bonded to each other. 66, the optical path controller 52, the field lenses 53, 54, 55, and the projection lens 97. As shown in FIG. The first prism 62 inclined surface is mirror coated, and there is a first coating 67 coated to reflect the red light at the junction of the second and third prisms 63 and 64, The junction of the third and fourth prisms 64 and 65 has a first coating 67 coated to reflect blue light, and the junction of the third and fourth prisms 64 and 65 is blue light. There is a second coating 68 coated to reflect light. The fifth prism 66 has a coating portion 96 coated with aluminum except for the hole 95. The field lenses 53, 54, and 55 are bonded to the second, third, and fourth prisms 63, 64, 65 and are close to the optical path controller 52 to reflect reflected light to the fifth prism ( The hole 95 of the image 66 is imaged without loss.

In the above, the light source 51 emits a light beam having high luminance white light.

The first prism reflects the light emitted from the light source 51 in the mirror coating part 61. The first coating part 67 of the second and third prisms 63 and 64 reflects red light from the reflected white light, transmits green and blue light, and the third and fourth prisms 64. The second coating portion 68 of 65 reflects blue light from green and blue light and transmits green light. Therefore, the incident white light can be separated into red, blue and green light without being lost. In the above, each prism has a refractive index of about 1.5 degrees.

The optical path controller 52 is composed of first, second and third actuator panels 67, 71, 73. The first, second and third actuator panels 69, 71 and 73 are panels (not shown) in which M x N transistors (not shown) are embedded and electrically connect these transistors to the outside. Actuators 81, 83, 85 and mirrors 86, 87, 88 are mounted on the driving substrates 75, 77, 79 formed with the. The actuators 81, 83, 85 are made of a thin film of piezoelectric or electrodistoric ceramic and are driven by an image signal applied from an external circuit (not shown) through transistors and pads. In addition, the mirrors 86, 87, 88 are inclined by the driving of the actuators 81, 83, 85. Actuators 81, 83, 85 and mirrors 86, 87, 88 correspond to the pixels, which are separated from the second and fourth prisms 63 and 65 and are incident red and green, respectively. The blue light corresponds to the respective pixels by the mirrors 86, 87 and 88 and adjusts and reflects the light path. The movement distance of the light between the first prism and the actuator panels 69, 71 and 73 is the same so that the light of each color corresponding to any same pixel is simultaneously illuminated by the same image signal. When the actuators 81, 83, 85 are not driven in the above, the hole 95 cannot be notified while the one side edge of the light formed in the fifth prism 66 coincides with the other edge of the hole 95. . However, when driven, only the light of the corresponding color is allowed to pass through the light transmission area 95 in proportion to the inclination angle to adjust the light density.

The field lenses 53, 54 and 55 are bonded to and fixed to the second, third and fourth prisms 63 and 64 and 65, respectively, and the first, second and third actuator panels respectively. Located in front of the fields 69, 71 and 73, it is desirable to have a large reflection angle so that the light reflected from the mirrors 86, 87 and 88 is not lost and the light path is reduced.

The projection lens 97 passes through the hole 95 of the fifth prism 66 to project the orphans of various colors, each of which has been adjusted in the amount of light, onto the screen 99.

In the projection image display device 50 having the above-described structure, the white light having high luminance is emitted from the light source 51 and the red, blue, and green light is emitted by the first coating part 67 and the second coating part 68. Are separated. Separated red, blue and green light passes through the field lenses 53, 54 and 55 and is incident perpendicularly to the first, second and third actuator panels 69, 71 and 73 The optical path is adjusted and reflected by the mirrors 86, 87, 88 of the first, second, and third actuator panels 69, 71, 73. The color light reflected by the optical path is adjusted to travel in the direction opposite to the incident direction to pass through the light transmission region 95 of the fifth prism 66.

In the above, when the image signal is not applied to the first, second and third actuator panels 69, 71 and 73, the reflected light is reflected at the same angle as the incident light, so that the coating portion of the fifth prism 66 96 is formed and no light is transmitted to the projection lens 97. However, when the image signal is applied, the reflected light changes the optical path for each pixel unit and passes through the hole 95 of the fifth prism. In this case, the hole 95 is proportional to the inclination angles of the mirrors 86, 87, and 88. Will pass through. Therefore, the light formed in the fifth prism 66 may or may not pass through the hole 95 depending on the presence or absence of an image signal, resulting in contrast. In addition, when the image signal is maximized, the inclination angles of the mirrors 86, 87 and 88 of the first, second and third actuator panels 69, 71 and 73 are maximized and reflected. All of the light passes through the hole 95 of the fifth prism 66.

If the actuators 81, 83, 85 of the first, second and third actuator panels 69, 71, 73 are formed by a thin film process, the mirrors 86, 87, 88 are formed. ) Is inclined from about 4º to 5º. Therefore, the angle between the path of the light reflected by the first, second and third actuator panels 69, 71 and 73 and the path of the incident light is increased. Accordingly, the first, second and third actuator panels 69, 71, 73 and the field lenses 89, 90 and 91 have a large angle between the incident light and the reflected light. Positioned closer to reduce the loss of light. Thus, the color light passing through the hole 95 of the fifth prism 66 is projected onto the screen 99 through the projection lens 97 to display a predetermined image.

As described above, the projection image display device using the prism according to the present invention, since the entire optical system is integrated through five prisms, it is possible to assemble the optical system with a precision of 0.01 ° and to reduce the defects during assembly In addition, there is an effect that can reduce the path difference of the optical system. In addition, the refractive index of the prism in the present invention has an effect that can reduce the effect of the angle when passing through the first and second coating portion to about 1.5 degrees.

As described above, the present invention has been described and illustrated with reference to the preferred embodiments, but it will be understood by those skilled in the art that various modifications may be made without departing from the spirit and scope of the present invention.

Claims (3)

A light source 51 that emits high-intensity white light, and first, second, third, fourth, and fifth prisms 62, 63, 64, 65, 66 that are integrally contact fixed. And first and second prisms 62 including field lenses 53, 54, 55, optical path adjusters 52, and projection lenses 97 that are in contact with and fixed to the second, third and fourth lenses. ) Has a mirror coating 61 reflecting light emitted from the light source 51, the white light reflected from the mirror coating 61 on the bonding surface of the second and third prism (63) (64) A first coating 67 is formed that reflects red light from and transmits green and blue light, and the first coating portion 67 is formed at the joining surfaces of the third and fourth prisms 64 and 65. A second coating 68 is formed to reflect blue light from the transmitted green and blue light and transmit green light, and the optical path controller 52 is separated from the first and second coatings 67 and 68. Red, green And reflecting blue light by adjusting optical paths for each unit pixel, and the fifth prism 66 passes through the optical path controller 52 to form an image of color light controlled by the optical path and to pass an amount of light proportional to the degree of adjustment of the optical path. A projection image display device using a prism characterized by having a hole (59). The method of claim 1, wherein the first, second, third, fourth and fifth prisms 62, 63, 64, 65 and 66 have a refractive index of about 1.5 degrees. Projection image display device using prism. The projection image display device using a prism according to claim 1, wherein the fifth prism (66) is aluminum coated except for the hole (95).