KR20080034275A - Apparatus and method for prism driving of display device - Google Patents

Abstract

An apparatus and a method for driving a prism of a video display are provided to prevent a light diffraction phenomenon occurring at an end portion of the iris by not using the iris. A controller(7) determines a gray scale of an inputted video signal, determines an optimum brightness, and sets a reflection angle of a prism(9). The prism adjusts brightness of a screen by selectively transmitting or reflecting light supplied from a light source(11). A prism driving unit(8) drives the prism at a reflection angle set by the controller. The controller determines the gray scale according to a white or black ratio of a screen. The controller adjusts a corresponding contrast ratio such that a frame with much white is brighter than a reference value and a frame with much black is darker than the reference value. The prism driving unit is a stepping motor or a piezoelectric driving element.

Description

Apparatus and method for prism driving of display device

1 is a block diagram showing a prism driving device of an imaging apparatus according to the present invention.

2 is a control flowchart illustrating a prism driving method of an imaging apparatus according to the present invention.

3 and 4 are views showing a light amount control state according to the prism driving of the present invention.

<Description of the symbols for the main parts of the drawings>

5: Image signal input unit 6: Image signal processor

7: control unit 8: prism driving unit

9: prism 10: video output unit

11 light source 12 condensing lens

13: color wheel 14: relay lens

15: DMD Panel 16: Projection Lens

17: screen

The present invention relates to an imaging apparatus, and more particularly, to a prism driving apparatus and method of an imaging apparatus for adjusting the amount of light using a prism.

In general, an image device such as a projector or a projection TV has an electric iris that opens and closes the aperture according to the brightness of the image, and increases the contrast ratio to 10,000: 1 or more.

The iris shutter is a device that can adjust the light source to increase the contrast ratio, and the conventional iris and the iris are implemented through a mechanical configuration or an LCD (lcd liquid crystal display) liquid crystal.

In the mechanical configuration, the aperture is configured to reduce or increase the amount of light by electric driving or manual driving. When implemented through the LCD liquid crystal, the amount of light transmitted is controlled by applying voltage to the liquid crystal of the LCD.

However, the conventional video device as described above, in the case of the shutter fine adjustment of the light was impossible, it is difficult to use the LCD projector or projection TV. In addition, since the light quantity of the continuous light is not controlled, it can be used only for the purpose of improving the contrast ratio by arbitrary adjustment. In addition, in the case of the iris, there is a problem that the amount of light is not precisely adjusted due to the diffraction phenomenon of the light irradiated to the end of the aperture.

Accordingly, the present invention is to solve the above-mentioned conventional problems, to enable fine control of the light, to control the amount of light continuously, and to prevent the diffraction phenomenon of light It is an object of the present invention to provide a prism driving device and method.

Prism driving apparatus of the video device according to the present invention for achieving the above object, the video signal input unit for receiving a video signal, receives the video signal from the video signal input unit to convert to a predetermined R, G, B video format A video device including an image signal processor and an image output unit for implementing a corresponding image on a predetermined screen according to R, G, and B image formats output from the image signal processor, wherein the gray scale of the input image signal is determined. A controller configured to determine an optimum brightness accordingly and set a reflection angle of the prism; A prism for selectively transmitting or reflecting the light supplied from the light source to adjust the brightness of the screen; And a prism driver for driving the prism at a reflection angle set by the controller.

For example, the controller determines the gray gray level according to a white or black ratio of the screen.

As another example, the controller adjusts the contrast ratio to make the frame having more white on the screen brighter than the reference value and the frame having many black ratios darker than the reference value.

As another example, the prism driver may be a stepping motor, or the prism driver may be a piezoelectric driver.

A prism driving method of an imaging apparatus according to the present invention includes an image signal input step of receiving an image signal; A video signal processing step of receiving a video signal from the video signal input step and converting the video signal into a predetermined R, G, B video format; In a control method of a video device comprising a video output step of implementing a corresponding video on a predetermined screen according to the R, G, B video format output from the video signal processor, determining the gray gray level of the input video signal A control step of determining a reflection angle of the prism by determining an optimum brightness accordingly; And driving the prism at the reflection angle set by the control step, thereby controlling the brightness of the screen by selectively transmitting or reflecting the light supplied from the light source.

As an example, the gray gradation is determined according to a white or black ratio of the screen.

As another example, the contrast ratio may be adjusted by making the white frame of the screen brighter than the reference value and the frame having a large black ratio darker than the reference value.

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

1 is a block diagram illustrating a prism driving apparatus of an imaging apparatus according to the present invention.

As shown, the present invention provides an image signal input unit 5, an image signal processing unit 6, a controller 7, a prism driver 8, a prism 9, an image output unit 10, a light source 11, The condenser lens 12, the color wheel 13, the relay lens 14, the DMD panel 15, the projection lens 16, and the screen 17 are included.

Common types of projectors include LCD, DLP and Lcos projectors.

For example, a DLP projector controls the reflection state by controlling the inclination of each mirror element using a DMD (Digital Mirror Device) panel, which is installed on a semiconductor memory cell and has hundreds of thousands of mirror elements each of which can control the inclination. do.

The DLP projector collects light emitted from a light source into a spot of a color wheel made up of a plurality of types of color filters configured to selectively pass any one of red, green, and blue light, and among the color filters. The light passing through either is irradiated to the DMD panel in the form of a parallel luminous flux, and is driven to project image light, which is light reflected from the DMD panel, onto the screen through a zoom projection lens. On the other hand, in the case of the DLP projector using the LED instead of the Lcos or the lamp there is also a structure using a drive element that emits R, G, B beams directly without applying the above-described color wheel.

Looking at the operation of each part of the video device of the present invention configured as described above, the video signal input unit 5 receives a video signal from outside the machine through a communication means such as air waves or cables.

The video signal processor 6 receives a video signal from the video signal input unit and converts the video signal into a predetermined R, G, and B video format. To this end, the video signal processor 6 is preferably composed of a conventional scaler.

The image output unit 10 implements a corresponding image on a predetermined screen according to the R, G, and B image formats output from the image signal processor 6. In the drawing, the image output unit 10 implements an image by driving the conventional color wheel 13 and the DMD panel 15, but in another example, which is not shown, the color wheel described above in the case of a DLP projector using an LED instead of an Lcos or a lamp It is also possible to implement an image by controlling the driving device that emits R, G, and B beams without applying.

The controller 7 determines a gray gray level of the input image signal, determines the optimum brightness accordingly, and sets the reflection angle of the prism. The controller 7 determines the gray gray scale according to the white or black ratio of the screen. In addition, the controller 7 adjusts the corresponding contrast ratio to make the frame having more white on the screen brighter than the reference value and the frame having many black ratios darker than the reference value.

To this end, the control unit 7 may be a CPU, MPU or microcomputer having a normal operation, comparison, determination function is applied, it is preferable to include a memory device such as a register or memory that can temporarily or permanently store the result value. Do.

The prism 9 selectively transmits or reflects the light supplied from the light source to adjust the brightness of the screen, and the prism driver 8 drives the prism 9 at a reflection angle set by the controller 7.

In addition, the light source 11 generates predetermined light, and the condenser lens 12 condenses the light emitted from the light source 11. The color wheel 13 is configured by combining a plurality of types of color filters to pass the light to create a plurality of color image light. The relay lens 14 adjusts the light to radiate the DMD panel 15 efficiently.

The DMD panel 15 reflects light, which is supplied from the light source 11 and passes through any one of the color filters constituting the color wheel 13, as the image light toward the screen 17. To this end, the DMD panel 15 is composed of a plurality of mirror elements (not shown) constituting the panel.

The image output unit 10 controls each mirror element of the DMD panel 15. The image output unit 10 outputs a gray scale signal used to control the inclination of each of the mirror elements of the DMD panel 15 according to the gray scale of each of the red, blue, and green colors represented by the video signal.

Here, the prism 9 may selectively transmit or reflect light supplied from the light source, and may be formed at the front end of the color wheel 13 as shown. Alternatively, the prism 21 may be formed at the front end or the rear end of the DMD panel 15.

2 is a control flowchart illustrating a prism driving method of an imaging apparatus according to the present invention, and FIGS. 3 and 4 are views illustrating a light amount adjusting state according to driving of a prism of the present invention.

As shown, the present invention provides a video signal input step (S101) for receiving a video signal; A video signal processing step of receiving a video signal from the video signal input step and converting the video signal into a predetermined R, G, B video format (S105); In the control method of a video device comprising a video output step (S106) for implementing a corresponding video on a predetermined screen according to the R, G, B video format output from the video signal processor, Gray gray of the input video signal A control step of determining a reflection angle of the prism by determining an optimum brightness accordingly; And driving the prism at the reflection angle set by the control step, and controlling the brightness of the screen by selectively transmitting or reflecting the light supplied from the light source.

As an example, the gray gradation is determined according to a white or black ratio of the screen. As another example, the contrast ratio is adjusted to make the frame having more white on the screen brighter than the reference value and the frame having many black ratios darker than the reference value (S104).

Referring to the operation of the present invention configured in this way in more detail as follows.

First, in a video signal input step (S101) of receiving a video signal, the video signal input unit 5 receives a video signal from outside the machine through a communication means such as airwaves or a cable.

Thereafter, a video signal processing step of receiving a video signal from the video signal input step and converting the video signal into a predetermined R, G, B video format is performed (S105).

Here, the video signal processing unit 6 composed of a normal scaler receives the video signal from the video signal input unit and converts the video signal into a predetermined R, G, B video format.

Thereafter, an image output step of implementing a corresponding image on a predetermined screen is performed according to the R, G, and B image formats output from the image signal processor (S106).

As shown, the image output unit 10 implements a corresponding image on a predetermined screen according to the R, G, B image formats output from the image signal processing unit 6, the conventional color wheel 13 and the DMD panel An image is driven by driving 15.

That is, in this embodiment, operations of the DMD panel 15 composed of a plurality of mirror elements are controlled by the image output unit 10 as a driver. The image output unit 10 controls the tilt state of each mirror element (not shown) constituting the DMD panel 15 according to the rotation state of the color wheel 13 and the video signal supplied from the outside of the DLP projector. To generate the image light projected onto the image.

The light emitted from the light source 11 is collected by the condenser lens 12, and the light is incident on the color wheel 13 so that the light is focused on the color wheel 13. The purpose of collecting and irradiating the light irradiated from the light source 11 is to reduce the time required to switch the color of the color wheel 13 by reducing the spot diameter of the luminous flux of the light.

Therefore, as described above, the color wheel 13 is disposed so that the light emitted from the light source 11 is collected by the condensing lens 12 and focus is generated thereon.

The color wheel 13 is constituted by a disk having a plurality of types of color filters, for example, to perform filtering of red, blue, green, and the like. The color wheel 13 is rotated at high speed by a motor (not shown) disposed on its central axis.

The light emitted from the light source 11 is condensed by the condensing lens 12, and the condensed light is irradiated on the color wheel 13, so that the irradiated light is red, blue by the rotation of the color wheel 13 Are filtered in order of, and green, and the filtered light is output to the relay lens 14.

The light filtered in such a way that the light has any one of red, blue and green by the color wheel 13 extends toward the DMD panel 15 while being expanded as shown in FIG. luminous flux) is adjusted by the relay lens 14 so that light is irradiated to the DMD panel 15 efficiently.

The light irradiated onto the DMD panel 15 is incident on each of the mirror elements (not shown) constituting the DMD panel 15. The image output unit 10 receives a gray level signal used to control the inclination of each of the mirror elements of the DMD panel 15 according to the gray level of each of the red (R), green (G), and blue (B) indicated by the video signal. The light reflected by each of the mirror elements toward the projection lens 16 is used as the image light to be projected onto the screen 17.

As another example, not shown, the image output unit 10 may implement an image by controlling the driving device that emits R, G, B beams directly without applying the color wheel described above in the case of a DLP projector using LEDs instead of Lcos or lamps. have.

On the other hand, in this state, the prism 9 adjusts the amount of light by selectively transmitting or reflecting the light supplied from the light source 11 at the front end of the color wheel 13.

That is, the controller 7 determines the gray gray level of the input image signal, determines the optimum brightness accordingly, sets the reflection angle of the prism 9 (S102), and sets the prism ( 9), a prism driving step of controlling the brightness of the screen by selectively transmitting or reflecting the light supplied from the light source is performed (S103).

For example, the gray gradation is determined according to the white or black ratio of the screen, and the contrast ratio is adjusted to make the frame having more white on the screen brighter than the reference value and the frame having many black ratios darker than the reference value (S104).

As shown in FIGS. 3 and 4, the reflection angle of the prism 9 is changed by changing the direction of light supplied from the light source 11 by placing the prism 9 at a total reflection angle to block or transmit the light. According to the amount of light.

For example, when the prism 9 is disposed at 45 degrees with respect to the incident light as shown in FIG. 3, the light quantity control is at a minimum (completely blocked) state, and is disposed at 90 degrees with respect to the incident light as shown in FIG. 4. In this case, it can be seen that the light quantity control is at the maximum (complete transmission) state.

To this end, the control unit 7 may configure an angle value of the prism according to the light amount as a table chart, store it in a predetermined register or a memory space, and further finely adjust the light amount displayed on the screen based on this.

Therefore, the reflection angle of the prism 9 can be adjusted to achieve a desired contrast ratio and brightness ratio.

At this time, the prism driver 8 drives the prism 9 at a reflection angle set by the controller 7, and the prism driver 8 is a stepping motor for fine adjustment of the prism angle, or a piezoelectric drive element. Is preferably.

In addition, the prism 9 is preferably formed at the front end of the color wheel 13, but as another embodiment, the prism 9 may be formed at the front end or the rear end of the DMD panel 15. .

Therefore, it is possible to finely adjust the light, making it convenient to use in DLP, LCD projectors or projection TVs, and to adjust the amount of light continuously so that it can be used for various adjustment purposes such as contrast ratio and brightness ratio. Since it is not used, it is possible to prevent diffraction of light generated at the end of the aperture.

The invention described above can be applied to LCD, DLP or LCoS projectors and projection TVs, as well as to flat panel display devices such as PDPs and LCDs, general CRT TVs, monitors and other video devices, and to analog TVs, digital TVs, and satellite TVs. The same applies to. In addition, it can of course be applied to all NTSC, PAL, SECAM method.

Although the preferred embodiments of the present invention have been illustrated and described above, the present invention is not limited to the above-described embodiments, and the present invention is not limited to the above-described embodiments without departing from the spirit of the present invention as claimed in the claims. Anyone skilled in the art can, of course, make various changes and make such changes as fall within the stated claims.

As described above, according to the prism driving apparatus and method of the imaging apparatus according to the present invention, it is possible to finely control the light, making it convenient to use in DLP, LCD projectors or projection TVs, and to adjust the amount of light continuously. Therefore, it can be used for various adjustment purposes such as contrast ratio and brightness ratio, and since the aperture is not used, there are various effects of preventing diffraction of light generated at the end of the aperture.

Claims (8)

A video signal input unit for receiving a video signal, a video signal processor for receiving a video signal from the video signal input unit, and converting the video signal into a predetermined R, G, B video format, and outputting the R, G, B video format output from the video signal processor. In the video device including a video output unit for implementing a corresponding video on a predetermined screen, A controller configured to determine a gray gray level of the input image signal, and determine an optimum brightness accordingly and set a reflection angle of the prism; A prism for selectively transmitting or reflecting the light supplied from the light source to adjust the brightness of the screen; And a prism driver for driving the prism at a reflection angle set by the controller. The method of claim 1, The control unit; The prism driving apparatus of the imaging apparatus, characterized in that the gray gradation is determined according to the white or black ratio of the screen. The method of claim 1, The control unit; The white-frame of the screen is brighter than the reference value, the frame of the black ratio is higher than the reference value, the contrast ratio of the apparatus, characterized in that for adjusting the contrast ratio. The method of claim 1, And the prism driving unit is a stepping motor. The method of claim 1, And the prism driving part is a piezoelectric driving element. A video signal input step of receiving a video signal; A video signal processing step of receiving a video signal from the video signal input step and converting the video signal into a predetermined R, G, B video format; In the control method of a video device comprising a video output step of implementing a corresponding video on a predetermined screen according to the R, G, B video format output from the video signal processor, A control step of determining a gray gray level of the input image signal, and determining an optimum brightness according to the reflection angle of the prism; And driving the prism at the reflection angle set by the control step to control the brightness of the screen by selectively transmitting or reflecting the light supplied from the light source. . The method of claim 6, The gray gradation may be determined according to a white or black ratio of a screen. The method of claim 6, The method of driving a prism of an imaging apparatus, characterized in that the contrast ratio is adjusted to make the white-rich frame brighter than the reference value and the black-frame is darker than the reference value.

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