KR100692093B1 - Projection System - Google Patents

Abstract

The present invention relates to a projection system. The projection system of the present invention includes a light source that emits white light, a dichroic mirror for separating light incident to the light source into red / green / blue, and a micro display device for displaying image information according to the light received from the dichroic mirror. A prism for synthesizing the displayed image information from each micro display device, and a variable shape reflective lens for displaying the image information at different positions of the screen by reflecting light from the prism as different optical axis inclinations over time bands; do. According to the present invention, it is possible to represent different image information corresponding to different time bands so that high resolution can be realized even when using a conventional micro display device having a low resolution.

X-prism, dichroic mirror, projection lens unit, variable shape reflective lens

Description

Projection System

1 is a view showing a projection system according to an embodiment of the present invention.

2 is a view showing the principle of operation of the variable shape reflective lens in the projection system according to the embodiment of the present invention shown in FIG.

3 is a view illustrating a principle in which focal points are formed at different positions by the variable shape reflective lens illustrated in FIG. 2.

 4A and 4B illustrate a micro display apparatus for sending image information to a projection lens apparatus according to the present invention.

5 illustrates a projection system according to another embodiment of the present invention.
<Description of the symbols for the main parts of the drawings>

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L: light source 11a, 11b: dichroic filter

12a, 12b: Mirror 13a, 13b, 13c: LCD
14: X-prism 15: projection lens unit
151: projection lens 153: variable shape reflective lens

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BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projection device for transmitting light incident from a reflective micro display device to a screen, and more particularly to a projection system capable of increasing the resolution by changing the shape of a variable reflective lens.

Recently, as the display device becomes lighter and becomes larger and larger, developing a large display device has become an important technical task in this field. One of the things developed with such a large screen display device is a projection TV. The projection TV requires high resolution as digital broadcasting becomes full-fledged, and a micro display device has been developed as one of the methods for solving the resolution problem.

The micro display apparatus refers to a small display having a required resolution as an information display device having a small screen of 1 inch or less diagonally. It can have resolutions of QVGA, VGA, SVGA, SVGA, SXGA, and UXGA on screens smaller than 1 inch diagonal, and the current resolution tends to increase and decrease in size. The microdisplay is classified into a transmissive type, a reflective type, and a light emitting type. The transmissive type is divided into a TFT LCD using high temperature polysilicon and a SOI (silicon on insulator) using a silicon wafer.

In addition, the reflective type uses a silicon wafer as a substrate, while the pixel electrode is a metal electrode with good reflectance, and a liquid crystal on silicon (LCOS) that utilizes liquid crystal in reflection mode or a micro metal electrode fabricated on the substrate is reflected. There is a digital micro-mirror display (DMD) for adjusting the angle.

It is an object of the present invention to provide a projection system for increasing the resolution of a micro display by having different shapes over time.

According to an embodiment of the present invention, a projection lens apparatus according to the present invention reflects a projection lens for receiving image information transmitted from a micro display apparatus and a signal received from the projection lens as different optical axis inclinations according to time bands. And a variable shape reflective lens, wherein the reflected signal as different optical axis tilts represent image information at different positions or pixels of the screen.

The micro display apparatus transmits different image information stored in two or more divided regions to the variable shape reflective lens at different time bands.

According to another suitable embodiment of the present invention, the variable shape reflective lens has a lens shape in which light is reflected, and the optical axis inclination is vertical, horizontal, or diagonal.

The panel storing the image information of the micro display device is rectangular or rhombus, and the panel is divided into an odd data area and an even data area, and transmits the image information in different time bands.

The difference D = L × tan (2 × θ) of the position where different image information is displayed on the screen becomes L, where L is the distance between the center of the variable shape reflective lens and the screen and θ is the tilt of the optical axis.

According to another aspect of the present invention, a projection system includes a light source emitting white light; a dichroic filter for separating light incident to the light source into red / green / blue (R / G / B); A micro display device corresponding to each dichroic filter for storing image information in light received from the dichroic filter; A prism for synthesizing the light storing the image information transmitted from each micro display apparatus; and a projection lens for receiving the light transmitted from the prism and transmitting the light received from the projection lens in units of pixels on the screen. And a projection lens device including a variable shape reflective lens, wherein the variable shape reflective lens can express different image information at different positions of the screen in different time bands by using a change in the optical axis inclination.

The micro display is a digital micro-mirror device panel (DMD), the prism is a total internal reflection prism (TIR prism), and the microprocessor device stores different image information in different areas at different times. Image information is transmitted to the projection lens unit in the band.

Hereinafter, the variable shape lens system according to the present invention will be described in detail with reference to the accompanying drawings, and any known or obvious matters are omitted or briefly described in the description of this embodiment. However, this is for a clear understanding of the invention and is not intended to exclude these from the scope of the invention.

1 is a view showing a projection system according to an embodiment of the present invention.

As shown in Fig. 1, in a projection system using a transmissive LCD, in particular a High Temperature Poly Silicon (HTPS) TFT liquid crystal panel, the light emitted from the light source L is red (R) by the dichroic mirrors 11a and 11b. ) / Green (G) / Blue (B). That is, the dichroic mirrors 11a and 11b reflect desired light. In FIG. 1, the red dichroic mirror 11a shows red (R) light and the green dichroic mirror 11b shows green (R). Will reflect light.

Dichroic mirrors that reflect only light in this selectively required wavelength range are known in the art. The light separated by each dichroic mirror 11a, 11b is synthesized in an X-prism or color cube 14 via an illumination lens LL. The X-prism or color cube 14 may be a known X-prism such as a form of reproducing the primary colors by combining the images separated by R, G, and B by dichroic mirrors into one again.

In more detail, the light reflected by the red dichroic mirror 11a is first incident on the X-prism 14 via the red LCD 13a through the first mirror 12a. The light reflected from the green dichroic mirror 11b is reflected by the green LCD 13b and the blue (B) light passing through the delay system RS is reflected by the second mirror 12b to provide the blue LCD 13c. It enters the X-prism 14 via. Each LCD 13a, 13b, 13c has the necessary image information and these image information is synthesized in the X-prism 14. The light synthesized by the X-prism 14 expresses necessary image information on the screen S via the projection lens device 15.

The projection lens apparatus 15 according to the present invention includes a projection lens 151 and a variable shape reflective lens 153. The variable shape reflective lens 153 is a lens whose shape changes with time, and operates to express different image information transmitted from the LCDs 13a, 13b, and 13c at different positions on the screen. The specific shape and operation of the variable shape reflective lens 153 is described in more detail below.

As described above, the projection lens according to the present invention is capable of improving the resolution by inserting the variable shape reflective lens 153 capable of improving the pixel between the micro displays LCDs 13a, 13b, and 13c and the screen S. It is a feature of the device 15. As a result, according to the system of the present invention, it is possible to display different image information at each position of the screen to display the image information in the number of pixels more than the number of pixels (Pixel) that the micro display MD can represent. This will increase the resolution.

2 is a view showing the operating principle of the variable shape reflective lens in the projection system according to the embodiment of the present invention shown in FIG.

As shown in Fig. 2, the variable shape reflective lens 153 is characterized in that the whole can be rotated from the initial position by the required angle. If the variable shape reflective lens 153 is rotated or tilted by θ ₁ with respect to the optical axis of the lens, between the initial focus formed on the screen S from the center of the variable shape lens 153 and the changed focus due to the tilting. The angle formed is θ ₂ . At this time, the following equation holds by the law of reflection.

θ ₂ = 2 × θ ₁

In addition, if the position change of the pixel due to the tilting of the variable shape reflective lens 153 on the screen S is D, the following equation holds.

D = L × tan (θ ₂ ) = L × tan (2 × θ ₁ )
Here, L represents the distance from the variable shape lens 153 to the screen S. FIG.

As shown in FIG. 2, three lights L1, L2, and L3 incident from the X-prism (see FIG. 1) through the projection lens (see FIG. 1) form a focal point at F1. That is, image information is displayed on the pixel of the screen located at F1. If the variable shape reflective lens is tilted after the focal point is formed at F1, the focal point is formed at F2 by three light sources L1, L2, and L3 coming from the same direction, and the difference in distance between the screens S between F1 and F2 is D. do. That is, image information is displayed at different positions of the screens F1 and F2. As described above, the variable shape reflective lens 153 according to the present invention may express image information by forming a focal point at different positions on the screen S with respect to light coming from the same direction over time.

Although FIG. 2 illustrates a case in which different focal points are formed in the vertical direction, a position where the focal point is formed on the screen S may also be in another direction by changing the tilt direction of the variable shape reflective lens 153 as necessary. . That is, by adjusting the tilt direction of the variable shape reflective lens 153, the focal point on the screen S may be formed along different directions. The direction of inclination, the inclination angle and the time difference in which the inclination is formed of the variable shape lens 153 may be made by a suitable adjusting device (not shown).

FIG. 3 is a diagram illustrating a principle in which focus is formed at different positions by the variable shape reflective lens illustrated in FIG. 2.

As shown in FIG. 3, the variable shape reflective lens 153 has a lens shape that reflects light, and focuses on the screen as the optical axis of the lens 153 changes from time to time from the position of (b) of FIG. 3. Are represented in different locations. FIG. 3A illustrates a form in which pixels are moved upwards and downwards. In the pixel of the screen of position (a) or (c) of FIG. 3, image information different from the image information displayed from the pixel of the screen of position (b) is displayed, whereby the projection lens apparatus according to the present invention has two resolutions. Doubling, or more, as needed.

4A and 4B illustrate a micro display apparatus 40 for sending image information to the projection lens apparatus according to the present invention.

As shown in FIG. 4A, the micro display apparatus 40 transmits an optical signal to a screen (see FIG. 1) by storing image information in units of pixels. 4A illustrates a micro display apparatus used in a known projection lens apparatus, and FIG. 4A (B) illustrates micro display apparatuses 40a and 40b used in a projection lens apparatus according to the present invention. will be.

In an embodiment of the present invention, the micro display apparatus stores each image information in an area divided into two parts. For odd data, image information is sent to the projection lens apparatus at a time corresponding to T = 0, and even data (Even Data) is sent to the projection lens apparatus at a time corresponding to T = 1. The projection lens device that receives the image information at the time corresponding to T = 0 sends the image information to the screen without tilting (see description related to FIG. 3), and transmits the image information at the time corresponding to T = 1 The received projection lens apparatus displays the image information on the screen in a state where the optical axis is inclined (see description related to FIG. 3).

By expressing different image information transmitted at such a divided time on the screen, it can be displayed on the screen with a higher resolution (more than twice) than the original resolution of the micro display device. However, the projection lens device according to the present invention does not necessarily need to be divided into two time intervals as described above.

The image information stored in the micro display apparatuses of different regions may be sent to the projection lens apparatus according to the present invention by dividing the data into several time intervals. As such, the projection lens apparatuses that receive image information of different regions at different times may express the respective image information on the screen by using the tilt of the optical axis corresponding to the different positions of the screen.

4B illustrates another embodiment of a micro display apparatus for sending an image signal to a projection lens apparatus according to the present invention. 4B illustrates a micro display apparatus 40 for transmitting an image signal to a conventional projection lens apparatus, and (B) micro display apparatuses 40a and 40b for transmitting an image signal to a projection lens apparatus according to the present invention. ) Is shown.

As shown in (b) of FIG. 4b, sending different image information at different times is the same as described with reference to FIG. 4a above except that the shape of the micro display panel is rhombus.

Those skilled in the art will appreciate that different types of panels can be divided into various time intervals to send different image information to the projection lens device.

5 is a view showing a projection system according to another embodiment of the present invention.

Referring to FIG. 5, non-polarized white light emitted from the light source L is incident on the color wheel 52 via the integrator 51. The integrator 51 makes the light emitted from the light source L uniform, and the color wheel 52 appropriately time-divisions the light incident from the integrator 51 according to the center wavelength. Do it.

For example, the white wheel 52 may be time-divisionally divided into magenta / yellow. The light time-divided according to the center wavelength is incident on the polarization beam splitter 54 via the illumination lens 53 and separated according to the wavelength to be used for the micro display, for example, a digital micro-mirror device panel 55. Is sent to. The polarization beam separator 54 separates the incident light into S waves and P waves, and transmits the S waves to the DMD panel 55. The DMD panel 55 converts the image information into P waves and sends them to the TIR prism 56. As described above, the DMD panel 55 sends signals in different areas at different time zones divided into two or more parts.

That is, the panel is divided into an odd data area and an even data area, and at time T = 0, image information of the odd data area is sent, and at T = 1, image information of the even data area is sent. The time domain T = 0 or 1 is a short enough time and limits the time at which human vision can be distinguished as different information. In addition, the time domain T can be divided into several time bands as necessary, as described above.

TIR prism 56 refers to a prism that totally reflects all light incident at a specific angle, and forms the light incident in the form of a light guide into a bright, glare-free, uniform wide area light and white or colored light. Enable the transfer. The TIR prism 56 may be any device known in the art. The image information guided by the TIR prism 56 reaches the variable shape reflective lens 572 via the projection lens 571 of the projection lens device 57.

The variable shape reflective lens 572 expresses the image information on the screen S by varying the optical axis inclination depending on whether the image information transmitted from the DMD panel 55 is a signal of an odd data area or an even data area. That is, the tilt of the optical axis may be alternately changed according to the time band in which the image information is sent. This optical axis tilt can be controlled using a suitable fine adjustment device (not shown) as already described. In this manner, the variable shape reflective lens 572 allows the signal transmitted from the DMD panel 55 to be displayed on the screen at twice or more resolutions as compared to known projection lens systems.

Although the apparatus according to the present invention has been described in detail above as an embodiment, it is obvious that a person skilled in the art can make modifications and modifications to the embodiment without departing from the scope of the technical idea of the present invention. . The scope of the invention is not limited by these modifications and variations, but only by the claims appended hereto.

The projection system according to the present invention makes it possible to tilt the optical axis in the left, right, up or down direction in time, thereby changing the position of the pixel in a certain direction on the screen over time. Accordingly, it is possible to represent different image information corresponding to different time bands, so that high resolution can be realized even when using a conventional micro display device having a low resolution. In addition, it is possible to increase the resolution without inserting an additional component for pixel enhancement, thereby reducing the weight or thinning of the entire projection system.

Claims (11)

A micro display device; And a variable shape reflecting lens for displaying the image information at different positions of the screen by reflecting the image information transmitted from the micro display apparatus with different optical axis inclinations according to time bands. The method of claim 1, And the micro display apparatus transmits different image information stored in two or more divided areas to the variable shape reflective lens at different time bands. The method of claim 1, The variable shape reflective lens is a projection system, characterized in that the shape of the lens is reflected light. The method of claim 1, And the tilt of the optical axis is vertical, horizontal, or diagonal. The method of claim 2, And the micro display device comprises a square or rhombus shaped panel. The method of claim 5, wherein And the panel divides the odd data area and the even data area and displays image information in different time bands. The method of claim 1, The variable shape reflective lens displays image information at different positions by L × tan (2 × θ) when the distance between the center of the variable shape reflective lens and the screen is L and the inclination of the optical axis is θ. Projection system. A light source emitting white light; A dichroic mirror for separating light incident to the light source into red / green / blue (R / G / B); A micro display device displaying image information according to light received from the dichroic mirror; A prism for synthesizing the image information displayed from each micro display device; And And a variable shape reflecting lens for displaying image information at different positions of the screen by reflecting light from the prism with different optical axis inclinations over time bands. The method of claim 8, The micro display apparatus includes a digital micro-mirror device panel (DMD). The method of claim 8, And the prism is a TIR prism (Total Internal Reflection Prism). The method of claim 8, And the micro display apparatus stores different image information in different regions and transmits image information to the variable shape reflective lens at different time bands.

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