CN104730823A - White balance adjustment device and method suitable for DLP projector - Google Patents

Abstract

The invention discloses a white balance adjustment device and method suitable for a DLP projector. A PC is connected with the DLP projector, so that the DLP projector sequentially projects out red, green and blue images. The DLP projector corresponds to an illumination meter, and the illumination meter obtains the red, green and blue images projected out by the projector in real time and measures chromaticity coordinates and illuminations of the red, green and blue images respectively. The PC calculates sequence files of rotation duty ratios of a red lamp, a green lamp and a blue lamp and then leads the sequence files into the DLP projector. The DLP projector sets the rotation duty ratios of the red lamp, the green lamp and the blue lamp according to the sequence files, namely achieves the purpose of changing the light proportion of the red lamp, the green lamp and the blue lamp, and further adjusts colorific white balance. The white balance adjustment device is high in calibration accuracy and low in brightness loss. In addition, the whole operating process is simple and convenient, adjustment time is short, production efficiency is greatly improved, and production cost is reduced.

Description

A kind of white balance adjustment device and method being applicable to DLP projector

Technical field

The present invention relates to a kind of projector white balance adjustment device and method, particularly relate to a kind of wheel by adjustment RGB three lamp and turn DLP projector white balance adjustment device and the method that dutycycle realizes blank level adjustment.

Background technology

DLP projector, i.e. digital light process (Digital Light Procession) projector, be a kind of based on dmd chip as image device, by powerful light source irradiation on this image device, realize the shadow casting technique of projects images with reflected light.Dmd chip, i.e. digital micro-mirror wafer (Digital Micromirror Device) are CMOS silicon chips be made up of micromirror array.Each micromirror represents a pixel, driving micromirror to rotate, controlling the gray-scale value of each pixel, micromirror imaging under the driving of electric signal, afterwards by projecting picture by camera lens after the reflection of light source by electric signal.

The principle of the DLP projector generation color of one chip irradiates dmd chip surface by the light source (being generally red, green, blue three look) of colour, reflect the incident light according to the sequential of red (R), green (G), indigo plant (B) three coloured light after dmd chip forms gray level image, project picture via after shaping lens by camera lens, form coloured image.Due to LED light source, to have photochromic purity high, and colour gamut is wide, and can realize the color feature such as revolution at a high speed, be particularly useful for the DLP projector of one chip, the DLP projector of existing one chip adopts LED light source substantially.Because the individual luminescence efficiency of LED light source there are differences, under equal current condition, the illuminance of generation is different, and then causes produced image color there are differences.The white balance adjustment method of prior art, is mainly changed the luminous intensity of LED light source, to adjust the illuminance of LED light source, improves image color by the current impulse dutycycle of the driving circuit of adjustment LED light source.This type of method of adjustment process is comparatively complicated, simultaneously higher to the stability requirement of the driving circuit of LED light source.

Summary of the invention

The object of the invention is to the deficiency overcoming prior art, a kind of wheel by adjustment RGB three lamp is provided to turn the DLP projector white balance adjustment device that dutycycle realizes blank level adjustment, this device can adjust the white balance of DLP projector effectively, and method is practical, and stability is strong.

The technical solution adopted for the present invention to solve the technical problems is: a kind of white balance adjustment device being applicable to DLP projector, comprising:

PC, is used for processing the chromaticity coordinate obtained by red, green, blue image three-colo(u)r inputted and illumination, and calculates the sequential file that the wheel obtaining RGB three lamp turns dutycycle;

DLP projector, is used for projecting red, green, blue image three-colo(u)r, and turns dutycycle according to the wheel of sequential file adjustment RGB three lamp;

Illuminometer, is used for measuring the chromaticity coordinate of projects images and illumination;

Wherein, PC is connected with DLP projector, PC first control DLP projector projects red, green, blue image three-colo(u)r successively, control illuminometer obtain the chromaticity coordinate of corresponding redgreenblue image and illumination and return PC simultaneously, calculate the wheel obtaining RGB three lamp afterwards and turn dutycycle and after formation sequence file, sequential file imported DLP projector; DLP projector is corresponding with illuminometer, and illuminometer, when DLP projector projects goes out red, green, blue image three-colo(u)r, measures chromaticity coordinate and the illumination of red, green, blue image three-colo(u)r respectively; Illuminometer is connected with PC, and the chromaticity coordinate of measurement and illumination are passed to PC by illuminometer.

Preferably, described PC is before control DLP projector projects red, green, blue image three-colo(u)r successively, also comprise and monitoring the ray machine temperature of described DLP projector, after the ray machine temperature of DLP projector reaches systemic presupposition temperature, control DLP projector projects red, green, blue image three-colo(u)r successively.

Preferably, described PC is calculating after the wheel obtaining RGB three lamp turns dutycycle, and whether what the wheel also comprising verification RGB three lamp turned dutycycle drops on preset range, if the wheel of gained RGB three lamp turns dutycycle exceed preset range, then judges to adjust unsuccessfully; After sequential file is imported DLP projector by described PC, also comprise control DLP projector projects white image, and control the chromaticity coordinate of illuminometer acquisition white image and return to PC, the chromaticity coordinate of white is obtained check results with after target chrominance coordinates value by PC.

Preferably, also comprise tool palette, it is used for carrying out the mutual conversion between USB interface signal and I2C interface signal or SPI interface signal; Described PC is connected with described DLP projector by this tool palette; Described tool palette is connected with described PC by USB interface, described tool palette is connected with described DLP projector with SPI interface by I2C interface, described PC is transmitted control signal to described DLP projector by the I2C interface of tool palette, and described PC writes described sequential file by the SPI interface of tool palette to described DLP projector.

Preferably, described RGB three lamp wheel turns dutycycle Duty _red, Duty _green, Duty _bluejudge that scope is as 18≤Duty _red≤ 57,26≤Duty _green≤ 68,10≤Duty _blue≤ 37.

Preferably, it is characterized in that: described RGB three lamp wheel turns dutycycle Duty _red, Duty _green, Duty _bluemeet following formula:

Ratio_rbc=Lux _red/ Lux _blue

Ratio_gbc=Lux _green/ Lux _blue

$a=\frac{\mathrm{Ratio}\_\mathrm{rbc}}{\mathrm{Ratio}\_\mathrm{rb}0}$

$b=\frac{\mathrm{Ratio}\_\mathrm{gbc}}{\mathrm{Ratio}\_\mathrm{gb}0}$

Wherein, x _red, y _red, Lux _redfor chromaticity coordinate and the illumination of the red image of DLP projector; x _green, y _green, Lux _greenfor chromaticity coordinate and the illumination of the green image of DLP projector; x _blue, y _blue, Lux _bluefor chromaticity coordinate and the illumination of the blue image of DLP projector; x _target, y _targetfor the chromaticity coordinate of ideal white field that will reach; Dr, dg, db are that original acquiescence RGB three lamp wheel of DLP projector turns dutycycle.

Preferably, described tool palette is also connected with the fan control interface of described DLP projector, to control the radiator fan of projector.

Preferably, the measurement point of described illuminometer to image chroma coordinate and illumination is the central point of image.

Be applicable to a white balance adjustment method for DLP projector, comprise the following steps:

A) DLP projector projects red, green, blue image three-colo(u)r successively;

B) chromaticity coordinate and the illumination of red, green, blue image three-colo(u)r is obtained successively;

C) wheel that the chromaticity coordinate of red, green, blue image three-colo(u)r that obtained by illuminometer of PC and luminance calculation obtain RGB three lamp set required for DLP projector turns dutycycle;

D) PC turns dutycycle formation sequence file according to the wheel calculating RGB three lamp obtained and sequential file is imported DLP projector.

Also comprise before described a) step: the ray machine temperature of PC to DLP projector is monitored, until ray machine temperature carries out subsequent step after reaching preset temperature;

Described c) step and d) also to comprise between step: the wheel of PC to RGB three lamp turns dutycycle and judges, the wheel of verification RGB three lamp turns dutycycle and whether drops on preset range, if the wheel of gained RGB three lamp turns dutycycle and exceeds preset range, then judge to adjust unsuccessfully;

Described d) also comprise after step: PC control DLP projector projects white image, and control the chromaticity coordinate of illuminometer acquisition white image and return to PC, the chromaticity coordinate of white is obtained check results with after target chrominance coordinates value by PC.

The invention has the beneficial effects as follows:

Be connected with DLP projector by PC, project red, green, blue image three-colo(u)r successively to make it; DLP projector is corresponding with illuminometer, and illuminometer Real-time Obtaining projector projects goes out red, green, blue image three-colo(u)r, and measures chromaticity coordinate and the illumination of red, green, blue image three-colo(u)r respectively; PC calculates the sequential file that the wheel obtaining RGB three lamp turns dutycycle, afterwards sequential file is imported DLP projector; The wheel that DLP projector arranges RGB three lamp according to sequential file turns sequential, namely reaches the object changing redgreenblue light ratio example, and then have adjusted the white balance of color.White balance adjustment device calibration accuracy of the present invention is high, and the chromaticity coordinate precision of test result can reach ± and 0.01, and do not reduce the power of LED light source, intensity loss is little; Meanwhile, integrated operation process is easy, and be convenient to producers and operate, regulation time is short, drastically increases production efficiency, reduces production cost.

Accompanying drawing explanation

Fig. 1 is theory diagram of the present invention;

Fig. 2 is the theory diagram of tool palette part of the present invention;

Fig. 3 is workflow diagram of the present invention.

Embodiment

Embodiment

Shown in Figure 1, a kind of white balance adjustment device being applicable to DLP projector, comprising:

PC 1, is used for processing the chromaticity coordinate obtained by red, green, blue image three-colo(u)r inputted and illumination, and calculates the sequential file that the wheel obtaining RGB three lamp turns dutycycle;

DLP projector 2, is used for projecting red, green, blue image three-colo(u)r, and turns dutycycle according to the wheel of sequential file adjustment RGB three lamp;

Illuminometer 3, is used for measuring the chromaticity coordinate of projects images and illumination;

Wherein, PC 1 is connected with DLP projector 2, PC 1 first control DLP projector 2 projects red, green, blue image three-colo(u)r successively, control illuminometer 3 obtain the chromaticity coordinate of corresponding redgreenblue image and illumination and return PC 1 simultaneously, calculate the wheel obtaining RGB three lamp afterwards and turn dutycycle and after formation sequence file, sequential file imported DLP projector 2; DLP projector 2 is corresponding with illuminometer 3, and illuminometer 3, when DLP projector 2 projects red, green, blue image three-colo(u)r, measures chromaticity coordinate and the illumination of red, green, blue image three-colo(u)r respectively; Illuminometer 3 is connected with PC 1, and the chromaticity coordinate of measurement and illumination are passed to PC 1 by illuminometer 3.

Further, described PC 1 is before control DLP projector 2 projects red, green, blue image three-colo(u)r successively, also comprise and monitoring the ray machine temperature of described DLP projector 2, after the ray machine temperature of DLP projector 2 reaches systemic presupposition temperature, control DLP projector 2 projects red, green, blue image three-colo(u)r successively.

Further, described PC 1 is after the wheel calculating acquisition RGB three lamp turns dutycycle, whether what the wheel also comprising verification RGB three lamp turned dutycycle drops on preset range, if the wheel of gained RGB three lamp turns dutycycle exceed preset range, then judges to adjust unsuccessfully; After sequential file is imported DLP projector 2 by described PC 1, also comprise control DLP projector 2 and project white image, and control illuminometer 3 and obtain the chromaticity coordinate of white image and return to PC 1, the chromaticity coordinate of white is obtained check results with after target chrominance coordinates value by PC 1.

Further, also comprise tool palette 4, it is used for carrying out the mutual conversion between USB interface signal and I2C interface signal or SPI interface signal; Described PC 1 is connected with described DLP projector 2 by this tool palette 4; Described tool palette 4 is connected with described PC 1 by USB interface, described tool palette 4 is connected with described DLP projector 2 with SPI interface by I2C interface, described PC 1 is transmitted control signal to described DLP projector 2 by the I2C interface of tool palette 4, and described PC 1 writes described sequential file by the SPI interface of tool palette 4 to described DLP projector 2.

Further, described RGB three lamp wheel turns dutycycle Duty _red, Duty _green, Duty _bluejudge scope as

18≤Duty _red≤ 57,26≤Duty _green≤ 68,10≤Duty _blue≤ 37.

Further, it is characterized in that: described RGB three lamp wheel turns dutycycle Duty _red, Duty _green, Duty _bluemeet following formula:

Ratio_rbc=Lux _red/ Lux _blue

Ratio_gbc=Lux _green/ Lux _blue

$a=\frac{\mathrm{Ratio}\_\mathrm{rbc}}{\mathrm{Ratio}\_\mathrm{rb}0}$

$b=\frac{\mathrm{Ratio}\_\mathrm{gbc}}{\mathrm{Ratio}\_\mathrm{gb}0}$

Wherein, x _red, y _red, Lux _redfor chromaticity coordinate and the illumination of the red image of DLP projector 2; x _green, y _green, Lux _greenfor chromaticity coordinate and the illumination of the green image of DLP projector 2; x _blue, y _blue, Lux _bluefor chromaticity coordinate and the illumination of the blue image of DLP projector 2; x _target, y _targetfor the chromaticity coordinate of ideal white field that will reach; Dr, dg, db are that original acquiescence RGB three lamp wheel of DLP projector 2 turns dutycycle.

Further, described tool palette 4 is also connected with the fan control interface of described DLP projector 2, to control the radiator fan of projector.

Further, the measurement point of described illuminometer 3 pairs of image chroma coordinates and illumination is the central point of image.

Described tool palette 4 adopts model to be the chip of STM32F103, and its theory diagram as shown in Figure 2, mainly realizes following functions:

Be connected with PC 1 by USB interface, transmission of control signals and data; Be connected with projector by I2C interface, transmit the control signal received by PC 1; Be connected with the memory device of projector by SPI interface, by the memory device of the sequential file write projector received by PC 1; Monitoring projector ray machine temperature, and measurement data is returned to PC 1; Projector radiating fan swicth is controlled.

Described illuminometer 3 adopts model to be the illuminometer of CL-200A.

Shown in Figure 3, the course of work of the present invention is as follows:

1, the ray machine temperature of PC 1 pair of DLP projector 2 is monitored, and starts to detect when ray machine temperature reaches preset temperature;

2, PC 1 is transmitted control signal by tool palette 4, red, green, blue image three-colo(u)r is projected successively to make DLP projector 2, and the red, green, blue image three-colo(u)r that the control illuminometer 3 Real-time Obtaining projector projects that transmits control signal goes out, and measure chromaticity coordinate and the illumination of red, green, blue image three-colo(u)r respectively; x _green, y _green, Lux _greenfor chromaticity coordinate and the illumination of the green image of DLP projector 2; x _blue, y _blue, Lux _bluefor chromaticity coordinate and the illumination of the blue image of DLP projector 2; x _target, y _targetfor the chromaticity coordinate of ideal white field that will reach;

3, the redgreenblue that obtains of PC 1 turns dutycycle in conjunction with the wheel of formulae discovery RGB three lamp, is respectively Duty _red, Duty _green, Duty _blue;

4, PC 1 is to calculated Duty _red, Duty _green, Duty _bluejudging, as calculated the RGB three lamp dutyfactor value of gained beyond tolerance interval, then judging that light source goes wrong, need to change;

5, in sequential file storehouse, select corresponding sequential file, and write in DLP projector 2 by tool palette 4;

6, PC 1 controls projector projects by tool palette 4 and goes out white picture, reads the test result of illuminometer 3, the chromaticity coordinate of obtained chromaticity coordinate and ideal white field is compared, to judge whether successfully blank level adjustment.

Above-described embodiment is only used for further illustrating a kind of white balance adjustment device being applicable to DLP projector of the present invention; but the present invention is not limited to embodiment; every above embodiment is done according to technical spirit of the present invention any simple modification, equivalent variations and modification, all fall in the protection domain of technical solution of the present invention.

Claims (10)

1. be applicable to a white balance adjustment device for DLP projector, it is characterized in that: comprising:

PC, is used for processing the chromaticity coordinate obtained by red, green, blue image three-colo(u)r inputted and illumination, and calculates the sequential file that the wheel obtaining RGB three lamp turns dutycycle;

DLP projector, is used for projecting red, green, blue image three-colo(u)r, and turns dutycycle according to the wheel of sequential file adjustment RGB three lamp;

Illuminometer, is used for measuring the chromaticity coordinate of projects images and illumination;

Wherein, PC is connected with DLP projector, PC first control DLP projector projects red, green, blue image three-colo(u)r successively, control illuminometer obtain the chromaticity coordinate of corresponding redgreenblue image and illumination and return PC simultaneously, calculate the wheel obtaining RGB three lamp afterwards and turn dutycycle and after formation sequence file, sequential file imported DLP projector; DLP projector is corresponding with illuminometer, and illuminometer, when DLP projector projects goes out red, green, blue image three-colo(u)r, measures chromaticity coordinate and the illumination of red, green, blue image three-colo(u)r respectively; Illuminometer is connected with PC, and the chromaticity coordinate of measurement and illumination are passed to PC by illuminometer.

2. a kind of white balance adjustment device being applicable to DLP projector according to claim 1, it is characterized in that: described PC is before control DLP projector projects red, green, blue image three-colo(u)r successively, also comprise and monitoring the ray machine temperature of described DLP projector, after the ray machine temperature of DLP projector reaches systemic presupposition temperature, control DLP projector projects red, green, blue image three-colo(u)r successively.

3. a kind of white balance adjustment device being applicable to DLP projector according to claim 1, it is characterized in that: described PC is after the wheel calculating acquisition RGB three lamp turns dutycycle, whether what the wheel also comprising verification RGB three lamp turned dutycycle drops on preset range, if the wheel of gained RGB three lamp turns dutycycle and exceeds preset range, then judge to adjust unsuccessfully; After sequential file is imported DLP projector by described PC, also comprise control DLP projector projects white image, and control the chromaticity coordinate of illuminometer acquisition white image and return to PC, the chromaticity coordinate of white is obtained check results with after target chrominance coordinates value by PC.

4. a kind of white balance adjustment device being applicable to DLP projector according to claim 1, is characterized in that: also comprise tool palette, and it is used for carrying out the mutual conversion between USB interface signal and I2C interface signal or SPI interface signal; Described PC is connected with described DLP projector by this tool palette; Described tool palette is connected with described PC by USB interface, described tool palette is connected with described DLP projector with SPI interface by I2C interface, described PC is transmitted control signal to described DLP projector by the I2C interface of tool palette, and described PC writes described sequential file by the SPI interface of tool palette to described DLP projector.

5. a kind of white balance adjustment device being applicable to DLP projector according to claim 2, is characterized in that: described RGB three lamp wheel turns dutycycle Duty _red, Duty _green, Duty _bluejudge that scope is as 18≤Duty _red≤ 57,26≤Duty _green≤ 68,10≤Duty _blue≤ 37.

6. a kind of white balance adjustment device being applicable to DLP projector according to claim 5, is characterized in that: described RGB three lamp wheel turns dutycycle Duty _red, Duty _green, Duty _bluemeet following formula:

Ratio_rbc=Lux _red/ Lux _blue

Ratio_gbc=Lux _green/ Lux _blue

$a=\frac{\mathrm{Ratio}\_\mathrm{rbc}}{\mathrm{Ratio}\_\mathrm{rb}0}$

$b=\frac{\mathrm{Ratio}\_\mathrm{gbc}}{\mathrm{Ratio}\_\mathrm{gb}0}$

Wherein, x _red, y _red, Lux _redfor chromaticity coordinate and the illumination of the red image of DLP projector; x _green, y _green, Lux _greenfor chromaticity coordinate and the illumination of the green image of DLP projector; x _blue, y _blue, Lux _bluefor chromaticity coordinate and the illumination of the blue image of DLP projector; x _target, y _targetfor the chromaticity coordinate of ideal white field that will reach; Dr, dg, db are that original acquiescence RGB three lamp wheel of DLP projector turns dutycycle.

7. a kind of white balance adjustment device being applicable to DLP projector according to claim 4, is characterized in that: described tool palette is also connected with the fan control interface of described DLP projector, to control the radiator fan of projector.

8. a kind of white balance adjustment device being applicable to DLP projector according to claim 1, is characterized in that: the measurement point of described illuminometer to image chroma coordinate and illumination is the central point of image.

9. be applicable to a white balance adjustment method for DLP projector, it is characterized in that: comprise the following steps:

A) DLP projector projects red, green, blue image three-colo(u)r successively;

B) illuminometer obtains chromaticity coordinate and the illumination of red, green, blue image three-colo(u)r successively;

C) wheel that the chromaticity coordinate of red, green, blue image three-colo(u)r that obtained by illuminometer of PC and luminance calculation obtain RGB three lamp set required for DLP projector turns dutycycle;

D) PC turns dutycycle formation sequence file according to the wheel calculating RGB three lamp obtained and sequential file is imported DLP projector.

10. a kind of white balance adjustment method being applicable to DLP projector according to claim 9, it is characterized in that: also comprise before described a) step: the ray machine temperature of PC to DLP projector is monitored, until ray machine temperature carries out subsequent step after reaching preset temperature;

Described c) step and d) also to comprise between step: the wheel of PC to RGB three lamp turns dutycycle and judges, whether what verification RGB three lamp wheel turned dutycycle drops on preset range, if the wheel of gained RGB three lamp turns dutycycle and exceeds preset range, then judge to adjust unsuccessfully;

Described d) also comprise after step: PC control DLP projector projects white image, and control the chromaticity coordinate of illuminometer acquisition white image and return to PC, the chromaticity coordinate of white is obtained check results with after target chrominance coordinates value by PC.