Purpose of the present invention just is to overcome the weak point of prior art, finishes the adjustment of white balance in a kind of full automatic mode, makes and safeguards deprofessionalization, reduces cost as much as possible under the prerequisite of the accuracy that guarantees to measure.
Characteristic feature of an invention: take into account the double factor of cost and technology, in rear-projection casing (or ray machine), photoelectric sensor has been installed and corresponding circuit part assigns to finish regulation and control.Propose and adopted the target control methods and the differential type background environment light cancellation of relativity system calibration mode, color separation formula self-balance regulating mode, predetermined value.
Key problem in technology of the present invention: basic circuit consists of: by photoelectric sensor, adaptive and D/A switch circuit part, numeric ratio and treatment circuit part, executive circuit part, input/output interface circuit etc. partly form, its groundwork flow process is; After inserting test signal, send red accordingly by projection ray machine (as CRT/LCD/DLP/LCOS/LASER class ray machine), blue, green test light signal, the photoelectric sensor that this light signal is put in the machine receives, the measurement numerical value of the signal of telecommunication that photoelectric sensor produced after adaptive and mould/number conversion circuit carries out digital-to-analogue conversion again numeric ratio and carry out in the treatment circuit with predetermined value relatively and output adjust instruction (can by IC bus command machine in related circuit carry out the white balance adjustment) and remove to control the response curve that executive circuit is adjusted the three primary colors light output of projection ray machine, constantly repeat said process, reach in the limit of permission until the error of measuring numerical value and predetermined value; Its basic technical characterictic have following some; Adopted relativity system calibration mode to carry out the calibration of system, adopt the color separation mode to carry out the regulation and control of white balance, adopted predetermined value to regulate and control pass breakpoint and excitation curve red, blue, green raster, adopted the differential data processing mode to eliminate bias light self-balance regulating is reached influence to system calibration as target data.
The key problem in technology of display unit of the present invention is: install and be provided with photoelectric sensor (containing electronic and firm banking), adaptive and D/A switch circuit part, numeric ratio and data processing circuit part, output output interface circuit part, lighting apparatus component and be used to install the preceding screen member and the casing of said modules in machine and in the circuit; Its groundwork process is as follows: by projection ray machine (as the CRT/LCD/DLP/LCOS/LASER class) sent red, blue, green test light signal, be placed in the reception of the photoelectric sensor in (between the fluoroscopic light-emitting area and screen of transmission or reflective light valves (LCD/DLP/LCOS) and screen or CRT pipe) light path in the casing, the signal of telecommunication that photoelectric sensor produced reaches at numeric ratio again after adaptive and mould/number conversion circuit carries out digital-to-analogue conversion and carries out in the treatment circuit and relatively also output control of predetermined value, and this difference electric weight removes to control executive circuit and adjusts the response curve of the three primary colors light of projection ray machine (can carry out the white balance adjustment by related circuit in the IC bus command machine); And then repeat said process again, reach in the limit of permission until the error of measuring numerical value and predetermined value; Its feature just is; Photoelectric sensor can also can be installed near the sidewall the screen in cabinet above the eyeglass of projection lens, also can be installed on the gap or sidewall between any two eyeglasses in the projection ray machine head group on show, or be installed in the zone between the internal reflection of projection ray machine and transmissive light valve and the lens group; Photoelectric sensor promptly can be hard-wiredly also can make its rotation and translation by electronic pedestal; On working method, adopted the relative system calibrating mode carry out system calibration, adopt the mode of color separation or timesharing to carry out the regulation and control of white balance, adopted predetermined value to regulate and control pass breakpoint and excitation curve red, blue, green raster, employing differential data processing mode as target data.
The details of above-mentioned key problem in technology can auspiciously state into:
Described relative system calibrating mode is meant: the test signal with one group of different brightness (can be equal uniform brightness, any standard such as GTG and off-gauge signal) make ray machine (also be light engine, optical projection system produces the components of projected light) luminous, and also to eliminate the influence of bias light in the differential data processing mode, with the outer photoelectric sensor of a machine locating that side surface (center or other position) is measured simultaneously with the photoelectric sensor in the machine and the data of both (in machines/machine outer sensor) compared at screen, change different test signals and will obtain different test datas, the data of being surveyed with the outer photoelectric sensor of machine are reference (drafting correction function illustrates referring to [figure two]), and and the data that the photoelectric sensor in the straightener is surveyed in the treatment circuit at numeric ratio, with obtain one with the outer consistent response curve of photoelectric sensor of machine, the algorithm of gained is correction function just, and this correction function is stored in the program storage in (numeric ratio and data processing circuit), when in normal white balance adjustment, the outer photoelectric sensor of machine is not access in, only carry out the test of light intensity by the photoelectric sensor in the machine, the data of this test will be revised by the correction function in the said procedure memory, these revised data are as final test data, because the calibration of all unit all is to finish with the outer photoelectric sensor (containing independently adaptive and D/A converting circuit) of same machine, good consistency will be obtained.To have an effect in the self-balance regulating afterwards, this algorithm is modified when system calibration next time.
Above-described color separation white balance observing and controlling mode is meant by the projection ray machine and gets final product red, blue, the green test light signal that timesharing also can be sent synchronously, when sending, timesharing only needs a photoelectric sensor, then need three photoelectric sensors to receive separately red, blue, green optical signal during synchronized transmission, so just can reach the purpose of color separation.When popping one's head in a photoelectric sensor and putting into the common signal channel of three coloured light between ray machine or camera lens and the screen, ray machine sends the light signal (red, blue, the green test light signal of the measurement that takes turns successively) of a color only simultaneously.When with a composite photoelectric sensor probe (containing a plurality of photoelectric sensors that are sensitive to different centre wavelengths) when putting into above-mentioned common signal channel (public domain of near the sidewall the cabinet inside screen and the lens group of LCD/DLP/LCOS ray machine and R, G between pixel light valve and the lens group, B light), ray machine can send composite coloured light signal (increased the complexity of processing of circuit at this moment but processing speed will be accelerated) simultaneously.Three photoelectric sensors probe can be placed on also that (there is such channel in three LCD/DLP/LCOS ray machines in red in the ray machine, blue, the green optical channel separately, zone between promptly red, blue, green glow valve device and three coloured light are synthetic, for the CRT ray machine then be separately camera lens the place ahead nearby, in the cavity in the lens assembly, between lens assembly and the filter and filter and CRT manage among the refrigerant between the glass bulb).
Described predetermined value control methods be meant one group with low-light level, middle brightness, high brightness video show pairing numerical value, this numerical value is decided by system itself, should be in the scope that system itself can regulate and control, corresponding to each given test signal, adjust the energized condition of ray machine, the measured numerical value of transducer and the difference of measured respective value are in advance entered in the scope of permission.In addition; When using as video wall, predetermined value can be a kind of trade-off of each unit to same signal measurement amount.After importing same test signal for each unit, photoelectric sensor probe in each unit may be measured different numerical value, the numerical value that each unit is surveyed carries out mutual communication (data of self is all passed to other all unit in each unit then, make each unit all will gather around the data of all unit), each single garden finally all will obtain predetermined value with same algorithm: the numerical value of maximum (little) value, weighted average or other reduction method gained of the desirable all unit of this predetermined value numerical value, adjust the energized condition (response curve) of whole ray machines.By digital interface also can be artificial change white balance predetermined value.
Described differential data processing mode is meant; The deviation that causes of cancellation bias light is wanted in the detection of light intensity in actual measurement, actual measured value should be effective signal light intensity and background light intensity sum, for eliminating the caused deviation of bias light, will measure the caused numerical value of bias light, therefore test signal need be placed Quan Heichang (signal level is in the blanking zone beyond the black level); Just ray machine is in cut-off state.Under/luminance, constantly switching then, to obtain two kinds of data for same test signal: the data under data under the cut-off state and the ray machine luminance, the data of off state are equivalent to the independent amount of influence of environmental background light, change different test signals and will obtain different test datas, whether the amount of influence of surround lighting changes then depends on environment fully.
Described test signal can be uniform grating or reticulate pattern grating or non-homogeneous bright field grating, the reason that the reticulate pattern grating is set is in order to adapt to the range of photoelectric sensor, and the high energized condition (high brightness) that so can reach ray machine when bright balance regulation is unlikely to exceed the range of photoelectric sensor again.
In the described motorised base promptly electromagnet to inhale moving device also can be control motor (can be stepping motor) drive unit, after the regulation process of white balance or system's correction finished, the photoelectric sensor probe was driven by motorised base and moves apart the light path channel.
Photoelectric sensor herein can be: (photodiode) of semi-conductor type, photosensitive solid material (photo resistance), photocell class material (active metal).
The invention will be further described with regard to preferred embodiment of the present invention below in conjunction with accompanying drawing:
Shown in [figure one]: this circuit needs just can use after the relative system calibrating mode is calibrated earlier.(1) be photoelectric sensor in the machine, (2) be adaptive and mould/number (A/D) change-over circuit, and (3) partly comprise for digital processing circuit: the numeric ratio that with CPU is core reaches (controlled quentity controlled variable output) circuit, procedure stores circuit than, arithmetic processing circuit.(4) be input/output interface circuit.(5) be the built-in test signal generator, (6) are other circuit module of unit: contain circuit such as image processing, scanning, power supply, (10) are system's correction photoelectric sensor (adaptive and mould/number (A/D) change-over circuit of self is (9)).The automatic self-balance regulating circuit part can directly insert the I of rear-projection machine
2C bus, all circuit parts can be directly connect with other circuit part of digital form and rear-projection or video wall element circuit, and when the unit carried out the regulation and control state of white balance, its concrete course of work was as follows:
After image processing module (6) inserts test signal (can be generated by the signal generator in the machine (5) and also can be sent into by machine external signal source), send red by projection ray machine (11) (as CRT/LCD/DLP/LCOS/LASER class ray machine) earlier, blue, green test light signal, for the influence of eliminating bias light need be adopted differential data processing mode (auspicious see that [figure three] illustrate), the photoelectric sensor (1) that this light signal is put in the machine receives, measurement numerical value after adaptive and mould/number conversion circuit (2) carries out digital-to-analogue conversion relatively reaches in numeral again and handles comparison operation and the output adjustment instruction of carrying out in the treatment circuit (3) with predetermined value (illustrating referring to [figure three]) again, and I is passed through in this instruction
2Carry out the white balance adjustment for image processing module (6) in the C bus command machine) remove to control the responsive state that the three primary colors light of projection ray machine is exported.Said process needs constantly to repeat, and reaches in the limit of permission until the error of measuring numerical value and predetermined value.
Shown in [figure two]: described relative system calibrating mode is meant: for each unit, exist different deviations always, when the test signal with one group of different brightness (can be equal uniform brightness, any standard such as GTG and off-gauge signal) make ray machine (also be light engine, optical projection system produces the components of projected light) luminous, will there be different results different unit to same test signal, need carry out objectivity to the response of the white balance detection system in the machine demarcates, for accomplishing this point, needing to measure simultaneously with the photoelectric sensor in the machine and the data of both (in machines/machine outer sensor) are compared from the side surface (center or other position) of screen with the outer photoelectric sensor of a machine (also needs carry out under the differential data processing mode, to eliminate the influence of ambient interferences light, auspiciously see that [figure three] illustrate), change different test signals and will obtain different test datas, the data of being surveyed with the outer photoelectric sensor of machine are reference (drafting correction function illustrates referring to [figure seven]), and and the data that the photoelectric sensor in the straightener is surveyed in the treatment circuit at numeric ratio, with obtain one with the outer consistent response curve of photoelectric sensor of machine, the correction function of gained will be retained in numeric ratio and reach in the program storage of treatment circuit, to have an effect in the self-balance regulating afterwards, when system calibration next time, be modified.When in normal white balance adjustment, the outer photoelectric sensor of machine is not access in, only carry out the test of light intensity by the photoelectric sensor in the machine, the data of this test will be revised by the correction function in the said procedure memory, these revised data are as final test data, because the calibration of all unit all is to finish with the outer photoelectric sensor (containing independently adaptive and D/A converting circuit) of same machine, good consistency will be obtained
Shown in [figure three]: the difference data processing mode is meant; The deviation that causes of cancellation bias light is wanted in the detection of light intensity in actual measurement, no matter the photoelectric sensor in the cabinet is installed in assorted one position, the outer light of machine all might a spot ofly enter in the machine, actual measurement result should be that signal light intensity and background light intensity sum are arranged, as long as measure the caused numerical value of bias light, just can utilize difference to calculate and eliminate the caused deviation of bias light.So test signal need be placed Quan Heichang (also be a black test signal, signal level is in the blanking zone beyond the black level), and the ray machine of this moment also just is in off state, and at this moment measured numerical value is the numerical value of bias light just.Because in the white balance adjustment process, the background light intensity may change, this just need constantly switch under test/off state, follows the tracks of the variation of bias light.Thereby will obtain two kinds of data: data under the test mode and the data under the off state, change different test signals and will obtain different test datas, and the amount of influence of surround lighting may be constant, be meant by the predetermined value control methods, corresponding to one group of low-light level, middle brightness, the pairing numerical value of high brightness vision signal, this numerical value is decided by system itself, should be in the scope that system itself can regulate and control, corresponding to each given test signal, adjust the energized condition of ray machine, the measured numerical value of transducer and the difference of measured respective value are in advance entered in the scope of permission.Can change the white balance predetermined value by digital interface.
When being combined into video curtain wall state, import same test signal for each unit, photoelectric sensor probe in each display unit can be measured numerical value separately, the numerical value that each unit is surveyed carries out mutual communication (data of self is all passed to other all unit in each unit then, can be undertaken by the serial data communication mouth between the unit, need a master control PC this moment or the innernal CPU of one of them unit is finished this point as master control, so all will there be the data of all unit each unit), each unit is all with these numerical value of same algorithm process, its algorithm can be: maximum (little) value of getting this sequence of values, the unified numerical value of weighted average or other reduction method gained is as predetermined value, adjust the energized condition (response curve) of whole ray machines, the measured numerical value of transducer and the difference of this final numerical value are entered in the scope of permission.
Shown in [figure four]: (21) are the unit rear box, (22) be screen assembly before the unit, (23), (24), (25) red, blue, green CRT lens assembly, (26), (27), (28) red for detecting, blue, the photoelectric sensor of green optical signal, mutatis mutandis photoelectric sensor when (29) being school, machine external system school, (30) be digital communication interface, (28) for having the photoelectric sensor of electronic pedestal, if the size of screen place grating is greater than the effective dimensions of forth screen plate, and on the sidewall that is installed in preceding screen inner core that the photoelectric sensor that enough big surplus inside when (shielding on the sidewall of member inner core before having enough big area to shine) is arranged can be fixed, and need not be equipped with on the electronic pedestal, shown in figure (28).But the more next need of situation are equipped with electronic pedestal.
Shown in [figure five] A is normal; Be near the curtain plate of preceding screen, to place a photoelectric sensor that has electronic pedestal, it is the public passage of light herein, the emitting and packing up of the photoelectric sensor that drives with a motor, the axle of motor (31) is rigidly connected with the bar (34) of transducer (33), by the rotation may command transducer immigration of motor and the effective coverage of shifting out projection ray.
Shown in [figure five] B is normal; It is another kind of way of realization; Rotating shaft (35) and rodmeter (34) are rigidly connected and can be around rotating with the fixing axis hole of pedestal, electromagnet (32) but inhale the iron body (38) of a moving linear slide, in the hole on traveller in the iron body (39) the insertion rodmeter (34), after electromagnet (32) energising, under the pulling of traveller (39), can make the photoelectric sensor on the rodmeter (34) move apart the projected light passage.Need to prove that motor also can match with travel switch, select stepping motor then simple and direct.
Need to prove that [figure five] A, [figure five] B can not use for detecting photoelectric sensor red, blue, green optical signal simultaneously with (26), (27), (28).
Shown in [figure five]: (41) are main imaging lens group (contain 3,4 eyeglasses and enclose the tube composition), and in use they are that light Jiao is adjusted in whole axial motion.(42) be optical filtering, the common space that constitutes a closure of the surperficial glass bulb of it and cavity (48) and CRT (43) holds cooling fluid (47).Other position that photoelectric sensor may be installed has: on the gap between any two eyeglasses in the lens group or the sidewall (44) of lens group sleeve, (45), or be installed in the zone between main imaging lens group and the optical filtering (46), also can be installed at optical filtering and CRT and manage in the cooling fluid (47) between (43) and be fixed on the inner surface of cavity (48).(49) be a kind of installation form of photoelectric sensor, drawn among the figure and stretched into photoelectric sensor and the lead-in wire in (46) in the zone.
Shown in [figure six]: photoelectric sensor can be installed in the dmd chip (micro mirror array) and the zone between the lens group in the DLP light engine (ray machine), shown in (61), when the micro mirror array on the dmd chip (63) during (will make light import uptake zone (46) in the ray machine by the rotation of micro mirror, these uptake zones just are the optimum positions that photoelectric sensor is installed) at the blanking pixel.(64) be lens group, (63) collimated light beam.The situation of LCD/LCOS and LASER projector also similarly.
A kind of utility system calibration regression curve has two amounts to need to determine shown in [figure seven]: the intercept after the calibration (zero point), slope after the calibration (normality multiplying power), just: the test signal with one group of different brightness (can be equal uniform brightness, any standard such as GTG and off-gauge signal) make ray machine (also be light engine, optical projection system produces the components of projected light) luminous, and also to eliminate the influence of bias light in the differential data processing mode, with the outer photoelectric sensor of a machine locating that side surface (center or other position) is measured simultaneously with the photoelectric sensor in the machine and the data of both (in machines/machine outer sensor) compared at screen, change different test signals and will obtain different test datas, the data of being surveyed with the outer photoelectric sensor of machine are reference (drafting correction function illustrates referring to [figure three]), and and the data that the photoelectric sensor in the straightener is surveyed in the treatment circuit at numeric ratio, with obtain one with the outer consistent response curve of photoelectric sensor of machine, the data that the photoelectric sensor of the algorithm of gained is surveyed are reference (drafting correction function illustrates referring to [figure four]), and and the data that the photoelectric sensor in the straightener is surveyed in the treatment circuit at numeric ratio, with obtain one with the outer consistent response curve of photoelectric sensor of machine, the algorithm of gained will be retained in numeric ratio and reach in the treatment circuit, to have an effect in the self-balance regulating afterwards, when system calibration next time, be modified.
Its a kind of practical system calibration regression function is: when ray machine sends certain luminous flux (establishing luminous flux is x), and Y
1, Y
2The photoelectric sensor of machine inside/outside through separately mould/resulting numerical value of number conversion circuit, A
1, A
2Be the value at zero point of machine inside/outside measuring system, its response curve equation is as follows:
Y
1=K
1X+A
1
Y
2=K
2X+A
2
K in the formula
1, K
2Be the normality value of system separately, it is determining the response sensitivity of system, in linear zone, can be approximately a constant.When with machine outer sensor system during as the standard of (relative meaning is arranged), final transformation result is:
The meaning of relativity calibration; Overcome the influence of the random deviation (inhomogenous dust covers and be aging) in device, installation and the use between each unit.