KR100513865B1 - Color-Wheel control apparatus for Image display system and the method thereof - Google Patents

Abstract

The present invention is an image display system using a liquid crystal display (LCD) or a liquid crystal on silicon (LcoS) to accurately control the wheel used for color separation or optical path separation to obtain the maximum brightness A color wheel control apparatus for a display system and a method thereof are provided. According to the present invention, the motor driving unit receives the motor control data to generate a signal for driving the motor, a wheel coupled to the motor shaft and controlled to rotate by a signal output from the motor driving unit, and the index information of the motor is detected. The sensor is divided into a fine adjustment step and a quick adjustment step according to the error range comparing the index sensor and the reference synchronization signal with the index information, and the motor control data according to each step is output to the motor driver through a separate line. It is configured to include a control unit, and the initialization step for controlling the motor when the power is applied, and the error comparison step to determine the error range by comparing the reference signal and the index information fed back from the motor to determine the fine adjustment step and the quick adjustment step , And to control the motor through separate lines according to the adjustment step. A motor adjustment step of outputting a motor data is included to allow the control method to be performed.

Therefore, according to the present invention, it is possible to precisely adjust the RPM and the deviation, thereby increasing the light quantity efficiency by using a wide range of the actual displayed area.

Description

Color-wheel control apparatus for image display system and the method

The present invention relates to a driving circuit and a method for improving luminance control in an image display system using a liquid crystal display (LCD) or a liquid crystal on silicon (LcoS), and is particularly used for color separation or optical path separation. An apparatus and method for precisely controlling a color wheel to obtain maximum luminance.

Typical projector display technologies include Liquid Crystal Display (LCD), Single Chip-Digital Light Processing (DLP), Cathode Ray Tube (CRT), and Liquid Crystal on Silicon (LcoS). Among these, CRT is a direct view projector, and liquid crystal display (LCD), single chip-digital light processing (DLP), and liquid crystal on silicon (LcoS) are used as projection projectors. CRT, which is mainly used for direct-view projectors, has R, G, B fluorescent spots formed on the fluorescent panel, black stripes are formed, and the electron beam emitted corresponding to the color image signal from the R, G, B electron gun is used for the shadow mask. When passing through and reaching a specific R, G, B fluorescent point, the corresponding fluorescent point emits light to display color. However, since the CRT has to be provided with R, G, and B fluorescent points for one pixel of the color image, the overall size of the CRT device must be large, and the size of the displayable screen is limited. On the other hand, the projection type LCD is the most common type of projector in which three liquid crystal panels speckle three colors of red, blue, and green through the pixels of the liquid crystal, and collect the light spectroscopically by the lens to produce an image. In addition, DLP integrates thousands of fine mirrors corresponding to pixels into a chip called a DMD (Digital Mirror Device) to incline the mirrors to reflect light to create an image from an image signal. LcoS is a new method that combines the technology of LCD and DLP, which means that LCD is integrated on a silicon wafer to form a circuit on it.Low power consumption, high resolution, and full color are possible, and the number of pixels is It is a situation that is being used a lot because it is possible to manufacture a high-resolution panel at a low price due to the advantage that the limit is small compared. Projection-type projectors employ a so-called AMA (Actuated Mirror Array) device that acts to modulate incident light or modulate the light path when a voltage corresponding to the image signal of the color image is applied, so that the source stops the light emitted from the light source into a uniform pattern. By a member, a field lens for condensing light shaped in a predetermined pattern through the source stop member, and an AMA device for reflecting the light condensed in the field lens at a reflection angle corresponding to the R, G, and B colors of the image signal. An optical modulation member, a projection stop member for positioning the light reflected by the optical modulation member to form an image on the screen, and a projection lens for displaying the light transmitted through the projection stop member on the screen. As is well known, in the optical modulation member of such a projection type projector, a color display device is required for displaying R, G, and B color light of a color image. An example of such a color display device is an R, G, B signal of a color image. AMA channel (usually provided corresponding to R, G, B color light) of the corresponding quantity and R, G, B color filter is adopted in front of each AMA panel, and the single color wheel A single-plate color display method for forming the R, G, B color filter area and controlling the rotation angle of the color wheel to obtain R, G, B color light is applied. Among them, a color display method employing a color wheel will be described with reference to FIGS. 1 and 2. 1 is a block diagram for driving the color wheel described above, and FIG. 2 is a detailed view of the color hill. As shown in the drawing, the method employing the color wheel includes a PLL (Phase Lock Loop) 11 and a control unit 10 and a control unit for controlling the motor driving unit 20 using position information fed back from the index sensor 40. Motor driving unit 20, which receives a clock (12) and RPM control (13) data necessary for driving the motor from the motor 10 and outputs the motor driving current 21 necessary for driving the motor, is coupled to the center of the motor and the motor driving unit It consists of a color wheel 30 that is rotated by the 20 and the index sensor 40 for feeding back the index information 41 by using a sensor to detect the motor speed and position information, the color wheel 30 by the motor driver 20 Is rotated in response to the R, G, and B signals of the color image to act to obtain R, G, and B color light from the light emitted from the light source. The color wheel 30 applied to such a projection image display system From the light source as shown in FIG. Receiving the incident bimsyat (Beam Shot) of white light sa yi color wheel is provided as a rotary filter to perform a rotation that corresponds to the R · G · B signals of the color image.

On the other hand, such a color wheel divides a single R filter region 30a, G filter region 30b, and B filter region 30c into constant regions, respectively, for the optical filter operation corresponding to the R, G, and B signals of the color image. The beam shot region 31 irradiated from the light is controlled to exist in any one of the R, G, B filter regions 30a, 30b, 30c.

Here, since the beam shot region 31 existing on the R, G, B filter regions 30a, 30b, and 30c of the color wheel is generally formed in a much smaller size than the respective filter regions, as shown in Fig. 2B. The color wheel 30 including the R, G, and B filter areas 30a, 30b, and 30c is rotated in the direction of the arrow (clockwise) by the motor driver 20, so that the beam shot area 31 is reproduced to reproduce the color image. When the synchronization portion for the color image corresponds to, for example, the boundary between the G filter region 30b and the B filter region 30c in the state of moving on the R, G, B filter regions 30a, 30b, 30c. The predetermined area 31a positioned in the G filter area 30b of the beam shot area 31, for example, acts as color noise of the projection image, resulting in deterioration in image quality. In other words, if the deviation is large, the display time is reduced, and thus it is difficult to obtain the maximum luminance.

Therefore, in order to prevent deterioration of color image quality in such a state that R, G, B color light is obtained by such a color wheel, a driving method of the color wheel which is synchronized with the R, G, B signal of the color image accurately is required. In other words, the RPM and the deviation must be finely controlled in the motor driving for image processing.

An object of the present invention is to provide a color wheel control apparatus and a method for improving light quantity efficiency by using a wide range of the actual displayed area to finely adjust RPM and deviation. .

The color wheel control apparatus of the image display system for achieving the above object, the motor driving unit for receiving the motor control data to generate a signal for driving the motor, and coupled to the motor shaft by the signal output from the motor driving unit A wheel that is controlled to rotate, an index sensor that detects and feeds back index information of the motor, and is divided into a fine adjustment step and a quick adjustment step according to an error range in which a reference synchronization signal and the index information are compared. It is configured to include a control unit for outputting data to the motor driving unit through a separate line.

The fine tuning step masks and outputs a predetermined clock, and the quick tuning step outputs RPM control data to control the motor.

Here, the control unit is an initial adjustment unit for controlling and stabilizing the initial motor, comparing the reference synchronization signal and the index information to determine the error range, the error comparison unit divided into a fine adjustment step and a quick adjustment step, variable by masking a predetermined clock And a clock control unit for outputting the control unit, a speed control unit for outputting RPM control data, and a synchronization display unit for displaying an operation state for each adjustment step.

In addition, the color wheel control method of the projection-type image display system driven by a motor for achieving the above object is an error range by comparing the initialization signal to control the motor when the power is applied, and the reference signal and the index information fed back from the motor And an error comparison step of dividing the micro adjustment step into a quick adjustment step, and a motor adjustment step of outputting motor data for controlling the motor through separate lines according to the adjustment step. .

In addition, it is preferable to further include a synchronization display step for displaying the operation state of each adjustment step so that the user can easily determine the current operation state.

Here, in the fine adjustment step, a predetermined clock is masked and output, and in the quick adjustment step, the RPM control data is output to control the motor.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. Figure 3 is a block diagram for explaining the driving of the color wheel of the present invention, Figure 4 is a state comparison diagram for determining the speed of the current motor by comparing the state of the index information and the reference synchronization signal, Figure 5 is the present invention using the above configuration Flow chart for driving the color wheel of Fig. 6 is a diagram showing an example of clock masking.

First, as shown in FIG. 3, an apparatus for driving the color wheel of the present invention includes a motor driving unit 200, a wheel 220, an index sensor 230, and a controller 100. The motor driving unit 200 receives the motor control data to generate a motor driving current 210 required for driving the motor to drive the motor coupled to the color wheel 220. The wheel 220 is coupled to a motor shaft (not shown) and is rotated by a clock (CLOCK) 160 and an RPM control 170 signal output from the motor driver 200, respectively. In addition, the color wheel 220 is rotated in response to the R, G, B signal of the color image to operate to obtain R, G, B color light from the light emitted from the light source. Since the detailed structure is provided in the same configuration as the conventional color wheel 30, description thereof will be omitted. The index sensor 230 extracts index information from the rotating motor and performs a function of feeding back the control unit 100. Typically, the index information is configured to attach and rotate a Hall element on one side of a rotating motor, and to install a detection sensor to detect and output a predetermined signal every time the Hall element is rotated. In addition, the control unit 100 compares the reference synchronization signal and the index information output from the index sensor 230, and divides the motor control data according to each step into a fine adjustment step and a quick adjustment step according to the error range. It is operated to output to the motor driving unit 200 through the line of. The control unit 100 outputs the initial rotation data to the motor at the time of power supply and stabilizes the initialization adjusting unit 110, and compares the reference synchronization signal with the index information to determine the error range and compares the fine adjustment step and the quick adjustment step. When the control unit 130 and the comparison unit 130 determine that the fine adjustment step is performed, the clock control unit (CLOCK mask) 140 and the comparator 130 rapidly adjust and output a mask by masking a predetermined clock to precisely control the motor. And a speed count changing unit 150 for outputting RPM control data to quickly control the motor, and a synchronization display unit 120 displaying an operation state for each adjustment step. . In detail, as shown in FIG. 4, the comparison unit 130 compares index information input from the reference signal Sync and the index sensor 230 to determine whether the current motor rotation speed is faster or later than the reference signal Sync. To judge. That is, the comparison unit 130 determines the presence or absence of a hall signal of the index information at the falling edge (a) and the rising edge (b) of the reference signal Sync. If the Hall signal occurs earlier than the falling edge (a), it is determined that the rotation of the motor is in a fast state and the Hall signal occurs later than the rising edge (b) as shown in (b). In this case, it is determined that the rotation of the motor is in a slow state. The error range is determined by detecting the width of the hall signal (the distance between the falling edge and the rising edge of the hall signal; x) and the distance y between the reference signal and the hall signal. It is determined whether it is a quick adjustment step or a fine adjustment step. In the initial comparison, it is first determined whether it is in a large error range, that is, a quick adjustment step, and then the motor is controlled to enter the fine adjustment step. Therefore, in the early stage, the steady state should be reached as soon as possible because it takes a long time to reach the steady state when the fine tuning is performed from the beginning. In this embodiment, the state of (a) is determined to be a fine adjustment step and the state of (c) is determined to be a quick adjustment step. If it is determined in the fine adjustment step, the clock mask (CLOCK mask) 140 masks and outputs a predetermined clock (CLOCK; 160), and if it is determined in the quick adjustment step, the speed count changing unit (SPEED counter changing unit; 150) Output the count data corresponding to the RPM, that is, RPM control 170 data to control the motor. In addition, a method of masking a predetermined clock is described in FIG. In general, the RPM count value is controlled quickly by transmitting a data value corresponding to 16 bits, but since the data value corresponding to the LSB of the data also operates with a large amount of change, the RPM control 170 data is used to finely adjust the motor. I cannot do it. Accordingly, in an embodiment of the present invention, the motor may finely adjust the duty of the clock by varying the duty of the clock 160 by using a principle that the motor reads data in synchronization with the transmitted clock. To ensure that For example, three clocks of a reference clock may be masked and transmitted as one clock pulse (masking part A of FIG. 6), and two masks (masking part B of FIG. 6) may be transmitted.

The operation of the color wheel control device of the image display system having the above configuration will be described below.

When power is applied in the initial state, the controller 100 reads initial data necessary for driving the motor from the initialization controller 110 and controls the RPM corresponding to a count value (counter value) required for initial driving in the speed count changer 150. (170) Data is output (S310). After the data output, it is determined whether the motor is stable (S320) and waits until it becomes stable (S330). After the stabilization, the index information 240 output from the index sensor 230 is input from the comparator 130 to determine an error range (Error) and compare with the preset first range value range1 (S340). ). The range value range1 is a value generally used when comparing a large error range for quickly controlling a motor and is set larger than the second range value range2 which is an error range of the fine adjustment step and is determined in advance and compared to the comparison unit 130. ) If the error range (Error) is smaller than the range value (range1) in step S340 and proceeds to the next step (S360) and if the error range (Error) is larger than the range value (range1), it is determined as a quick adjustment step and the motor rotation It is compared whether the state is a fast state ((a) of FIG. 4) or a late state (b) of FIG. 4 with respect to the reference signal (S350). Preferably, the control unit 100 may provide convenience to the user by displaying the state of the current motor in the quick adjustment step on the display device (not shown) in the synchronization display unit 120. If the error range (Error) is greater than the range value (range1) in step S340 to determine the degree of the error to determine the magnitude of the correction value of the motor according to each state (Error range determination; S351). That is, as shown in FIG. 4, the magnitudes of the x and y values are determined and used as data for motor correction. When the degree of error is determined in step S351, the comparator 130 corresponds to the RPM control 170 data in order to quickly control the motor from the speed count changing unit 150 to the motor driving unit 200. The counter value is transmitted and corrected (S352). If the error range (Error) is smaller than the first range value (1) by repeating step S340, the fixed counter value is fixed to complete the quick adjustment step (S370) and an error range (Error) to perform the fine adjustment step. Is less than the second range value range2 (S370). If the error range Error is smaller than the second range value range2 in step S370, the process proceeds to the next step S390. When the error range (Error) is greater than the second range value range2 in step S370, it is determined whether the rotational state of the motor is faster than the reference signal ((a) of FIG. 4) or late (b) of FIG. The determination is made as in step S351 (S380), and the degree of error is determined to determine the magnitude of the correction value of the motor according to each state (error range determination; S381). When the degree of error is determined in step S381, the comparator 130 transmits a clock CLOCK 160 determined according to the degree of error for fine adjustment from the clock mask 140 to the motor driver 200. Correction is performed (S352). In step S370, if the error range is smaller than the second range value range2, the transmitted masked clock value is fixed (S390).

While the invention has been described in detail only with respect to the described embodiments, it will be apparent to those skilled in the art that various modifications and variations are possible within the spirit of the invention, and such modifications and variations belong to the appended claims.

According to the color wheel control apparatus and method of the image display system according to the present invention as described above, it is possible to precisely adjust the RPM and the deviation to increase the maximum brightness by increasing the maximum brightness by using a wide area actually displayed.

1 is a block diagram for driving a general color wheel;

2 is a detailed view of a color wheel;

3 is a block diagram for driving a color wheel of the present invention;

4 is a state comparison diagram between index information and a reference synchronization signal;

5 is a flowchart for driving a color wheel of the present invention;

And,

6 is a diagram illustrating an example of clock masking.

* Description of symbols on the main parts of the drawings *

100: control unit 110: initialization adjustment unit

120: synchronization display unit 130: comparison unit

140: clock mask 150: speed count change unit

200: motor driving unit 220: wheel

230: Index sensor

Claims (6)

A motor driving unit receiving motor control data to generate a signal for driving the motor; A wheel coupled to a motor shaft and controlled to rotate by a signal output from the motor driver; An index sensor detecting and feeding back index information from the motor; And According to the error range comparing the reference synchronization signal and the feedback index information is divided into a fine adjustment step and a quick adjustment step, the motor control data according to each step is the clock line and the RPM control line through the separate line through the motor And a control unit for controlling the output to the driving unit. The method of claim 1, The fine adjustment step masks and outputs a predetermined clock, and the quick adjustment step outputs RPM control data to control a motor. The method of claim 1, wherein the control unit Initial adjustment unit for controlling the initial motor to stabilize; An error comparison unit comparing the reference synchronization signal with the index information to determine an error range and dividing it into a fine adjustment step and a quick adjustment step; A clock mask unit for masking and outputting a predetermined clock; A speed count changer outputting RPM control data; And And a synchronizing display unit for displaying an operation state for each adjustment step. In the color wheel control method of a projection type image display system driven by a motor, An initialization step of controlling a motor when power is applied; An error comparison step of comparing an index signal fed back from the motor with a reference signal to determine an error range and dividing it into a fine adjustment step and a quick adjustment step; And And a motor adjusting step of outputting motor control data for controlling the motor according to the adjusting step through a separate line to a clock line and an RPM control line, respectively. The method of claim 4, wherein And a synchronization display step of displaying an operation state of each adjustment step. The method of claim 4, wherein And controlling the motor by masking and outputting a predetermined clock in the fine adjustment step and outputting RPM control data in the quick adjustment step.