The present general inventive concept relates to a projection television, and more particularly, to a projection television having an improved color wheel to prevent heat generated from a color filter from being directly transmitted to a driving part.
Generally, a projection television applies a mechanism of a projector which uses a mirror and an optical lens to display an image by magnifying and projecting an image beam onto a screen. Such a conventional projection television is classified into a cathode ray tube (CRT) type, a liquid crystal display (LCD) type and a digital light processing (DLP) type depending on the type of display devices generating an image from signalized image information.
As shown in
The casing 110 comprises a front casing 111 and a rear casing 112 respectively provided in a front portion and a rear portion forming the external appearance. The front casing 111 comprises a front frame 113 coupled to the display 120 which forms the image; and a bottom frame 114 bent to a rear direction from the front frame 113 and to which the optical engine unit 130 and the lamp assembly 140 are mounted. In an upper portion of the rear casing 112 is provided the reflection mirror 121 reflecting the image beam from the optical engine unit 130 to the display 120, and a lower cover 115 coupled to the front casing 111 is provided in a lower portion of the rear casing 112.
The optical engine unit 130 comprises a color wheel 150 selectively sorting the light from the light source 141 into light of red (R), green (G) and blue (B); an optical engine part 131 comprising a light tunnel (not shown) uniformizing the light from the color wheel 150; a digital micromirror device (DMD) 132 as a display panel generating the image beam with the light transmitted from the optical engine part 131 by adjusting an angle of reflection for each pixel; and a projection lens 134 projecting the image beam generated by the DMD 132 to the reflection mirror 121.
The color wheel 150 of the optical engine part 131 is shaped like a disk, and comprises a driver 160 placed in a center portion of the color wheel 150 and driving the color wheel 150 to be rotated; and a plurality of color filters 161 radially formed centering on the driver 160 and selectively filtering the light from the light source 141 by light of red (R), green (G) and blue (B).
Thus, according to the conventional projection television 101, the color wheel 150 selectively sorts the light from the light source 141 by light of red (R), green (G) and blue (B), and the light tunnel uniformizes the light passing through the color wheel 150. The uniformized light forms the image beam by the DMD 132 and the image beam is projected to the display 120 through the projection lens 134 and the reflection mirror 121.
However, this conventional projection television 101 has problems in that the color filters 161 absorbing or reflecting the light from the light source 141 are placed on a traveling path of the light and adjacently coupled to the driver 160, and thus heat generated from the light source 141 is directly transmitted to the driver 160 by the color filter 161, causing the color wheel 150 to malfunction.
Further, the fan 142 of the conventional projection television 101 is provided only at the side portion of the lamp assembly 140, and thus inefficiently cools down the light source 141.
Accordingly, it is an aspect of the present general inventive concept to provide a projection television having a color filter absorbing heat generated from a light source disposed separately from a driver so as to prevent functional quality of a color wheel from being degraded due to the generated heat.
Another aspect of the present general inventive concept is to provide a projection television cooling down a front portion of a light source by using a color wheel placed in front of the light source.
Additional aspects and advantages of the present general inventive concept will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the general inventive concept.
The foregoing and/or other aspects and advantages of the present general inventive concept are achieved by providing a projection television comprising a light source emitting light; and a color wheel comprising a plurality of color filters provided in a front portion of the light source and transmitting the light from the light source, a driver rotatably driving the plurality of color filters, and a supporter having a first side coupled to the driver and a second side coupled to the plurality of color filters so as to rotatably support the plurality of color filters, the driver being provided in a center portion of the color wheel, the plurality of color filters being provided around an edge of the color wheel being spaced from the driver, and a heat barrier being provided between the driver and the plurality of color filters to prevent heat generated due to the plurality of color filters from being transmitted to the driver.
According to an embodiment of the present general inventive concept, the heat barrier forms a through hole to provide circulation of air.
According to an embodiment of the present general inventive concept, the heat barrier comprises a fan cooling down the light source.
According to an embodiment of the present general inventive concept, the fan is integrally formed with the supporter so as to rotate in accordance with rotation of the color wheel. According to an embodiment of the present invention, a fan is provided in an outer portion of the plurality of color filters and coupled to the color wheel to cool down the light source.
These and/or other ,aspects and advantages of the present general inventive concept will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompany drawings of which:
Reference will now be made in detail to the embodiments of the present general inventive concept, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout.
As shown in
The casing 10 comprises a front casing 11 and a rear casing 12 respectively placed in a front portion and a rear portion of the display 20 forming the external appearance.
The front casing 11 comprises a front frame 13 coupled to the display 20; and a bottom frame 14 bent rearward in the front frame 13 and to which the optical engine unit 30 and the lamp assembly 40 are coupled.
In an upper portion of the rear casing 12 is provided the reflection mirror 21 reflecting the image beam from the optical engine unit 30 to the display 20, and a lower cover 15 is provided in a lower portion of the rear casing 12 and coupled to the front casing 11. In a side of the lower cover 15 are provided an opening 16a injecting/ejecting the lamp assembly 40 therethrough, and an opening cover 16 coupled thereto and opening/closing the opening 16a.
The optical engine unit 30 comprises an optical engine part 31; a display panel 32; and a projection lens 34.
As shown in
The light emitted from the light source 41 is passed through the color wheel 50 rotatably provided in front of the light source 41 and sorted into light of red (R), green (G) and blue (B). The light sorted into a given color by passing through the color wheel 50 is uniformized by the light tunnel 36. Thus, the uniformized light passes through the lens group 38 comprising an image lens 38a and a cold mirror 38b, passing therethrough visible light and reflecting ultra violet rays, and almost in a parallel line goes to the display panel 32 via a first focus lens 37 focusing the incident light. The display panel 32 comprises a display device 32a and polarizers 32b provided in a front and a rear of the display device 32a, and generates an image from the light emitted from the light source 41 by employing the mechanism of the display device 32a. The light passed through the display panel 32 is passed through a second focus lens 33 and reflected by a reflection mirror inclinedly placed in a rear portion of the display 20 via the projection lens 34. The projection lens 34 comprises the reflection mirror 43 determining a focal length and the size of an image magnified corresponding to the focal length; and a plurality of lenses 44. Then, the reflected light is magnified and displayed on the display 20. Herein, the display panel 32 comprises a digital micromirror device (DMD), and creates the image from the incident light from the lens group 38 by adjusting a reflection angle for each pixel.
The color wheel unit 35 comprises the color wheel 50 selectively transmitting the light from the light source 41; a first cover 51 and a second cover 52 forming an external appearance of the color wheel 50; a wheel bracket 53 provided between the first cover 51 and the second cover 52 while mounting the color wheel 50 thereon, and comprising a light tunnel holder 58 supporting an end of the light tunnel 36; and a buffer 54 absorbing vibration from the color wheel 50 so as to prevent the vibration from being transmitted to the first cover 51 and the second cover 52 through the wheel bracket 53.
The first cover 51 and the second cover 52 are coupled by a first screw 57. Herein, the first screw(s) 57 passes through a respective first through hole 51a of the first cover 51 and is coupled to a respective first coupling hole 52a so as to connect the first cover 51 and the second cover 52. Further, the buffer 54 is coupled to the second cover 52 by a second screw(s) 59. Herein, the second screw(s) 59 passes through a respective second through hole 54a formed in the buffer 54 and is coupled to a respective second coupling hole 52b of the second cover 52 so as to connect the buffer 54 and the second cover 54. Here, a respective buffering washer 55 and a respective bushing 56 may be coupled to the respective second screw 59 so as to absorb the vibration of the color wheel 50 transmitted to the first cover 51 and the second cover 52. The second cover 52 may comprise a light through hole 52c in a side thereof to provide a traveling path of the light (refer to an arrow direction in
As shown in
The plurality of color filters 61 are placed on the traveling path of the light emitted from the light source 41, and each segment of the plurality of color filters 61 is composed of consecutive red, green and blue color filters. As previously described, the respective segments of the plurality of color filters 61 are coupled to the radial filter supporter 65, forming a ring shape. Typically, the color filter is made of flat glasses respectively coated with red, green and blue colors, and then each of the glasses is coupled to the supporter 62 after respectively being cut into a given size. Herein, the size of the color filter 61 can be reduced as long as the light on the traveling path (refer to the arrow in
The heat barrier 63 of the color wheel 50 comprises a fan 70 supplying air. The fan 70 may be integrally designed with the supporter 62 so as to be inclined at an angle of a given degree, and thus the fan 70 rotates according to the rotation of the color wheel 50 driven by the driver 60. Thus, as shown in
According to the foregoing embodiments of the present general inventive concept, a heat barrier formed like a through hole is provided between a color filter and a driver so that air can pass therethrough, thereby preventing heat transmitted to the color filter, from a light source, from being transmitted to the driver.
Meanwhile, the foregoing embodiments employ a digital micromirror device (DMD) as a display panel, but a liquid crystal display (LCD) or liquid crystal on silicon (LCOS) may be employed as the display panel.
Although a few embodiments of the present general inventive concept have been shown and described, it will be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the general inventive concept, the scope of which is defined in the appended claims and their equivalents.
Number | Date | Country | Kind |
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10-2004-0037300 | May 2004 | KR | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/KR05/00203 | 1/25/2005 | WO | 11/24/2006 |