CN1781318A - Liquid crystal projector having increased color accuracy - Google Patents
Liquid crystal projector having increased color accuracy Download PDFInfo
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- CN1781318A CN1781318A CNA2004800113305A CN200480011330A CN1781318A CN 1781318 A CN1781318 A CN 1781318A CN A2004800113305 A CNA2004800113305 A CN A2004800113305A CN 200480011330 A CN200480011330 A CN 200480011330A CN 1781318 A CN1781318 A CN 1781318A
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- 239000004973 liquid crystal related substance Substances 0.000 title description 4
- 238000000034 method Methods 0.000 claims abstract description 44
- 230000008569 process Effects 0.000 claims abstract description 26
- 238000012937 correction Methods 0.000 claims description 65
- 238000005259 measurement Methods 0.000 claims description 19
- 230000001915 proofreading effect Effects 0.000 claims description 15
- 238000006243 chemical reaction Methods 0.000 claims description 8
- 238000003384 imaging method Methods 0.000 claims description 6
- 230000004044 response Effects 0.000 claims description 3
- 238000012546 transfer Methods 0.000 claims description 2
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- 239000003086 colorant Substances 0.000 description 10
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- 230000003287 optical effect Effects 0.000 description 4
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N9/00—Details of colour television systems
- H04N9/12—Picture reproducers
- H04N9/31—Projection devices for colour picture display, e.g. using electronic spatial light modulators [ESLM]
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N9/00—Details of colour television systems
- H04N9/12—Picture reproducers
- H04N9/31—Projection devices for colour picture display, e.g. using electronic spatial light modulators [ESLM]
- H04N9/3102—Projection devices for colour picture display, e.g. using electronic spatial light modulators [ESLM] using two-dimensional electronic spatial light modulators
- H04N9/3105—Projection devices for colour picture display, e.g. using electronic spatial light modulators [ESLM] using two-dimensional electronic spatial light modulators for displaying all colours simultaneously, e.g. by using two or more electronic spatial light modulators
- H04N9/3108—Projection devices for colour picture display, e.g. using electronic spatial light modulators [ESLM] using two-dimensional electronic spatial light modulators for displaying all colours simultaneously, e.g. by using two or more electronic spatial light modulators by using a single electronic spatial light modulator
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N9/00—Details of colour television systems
- H04N9/12—Picture reproducers
- H04N9/31—Projection devices for colour picture display, e.g. using electronic spatial light modulators [ESLM]
- H04N9/3179—Video signal processing therefor
- H04N9/3182—Colour adjustment, e.g. white balance, shading or gamut
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N9/00—Details of colour television systems
- H04N9/64—Circuits for processing colour signals
- H04N9/73—Colour balance circuits, e.g. white balance circuits or colour temperature control
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Abstract
A method of color correcting a display is provided. Initially, uncorrected color values are used to produce images whose color characteristics are measured, specifically including luminance. Then, corrected color values are calculated such that the luminance of the corrected color values are the same as that produced by the uncorrected color values. The corrected color values are then used to produce images whose color characteristics are measured. A determination is made as to whether the corrected color values produce images having acceptable luminance and color characteristics, where acceptable luminance is based on the luminance obtained using the uncorrected color values. If not, a new set of corrected color values are produced. The process repeats until acceptable/desirable color characteristics are achieved. The method is useful for obtaining look-up table values, and for single-panel LCDs that use look-up tables. An interpolation technique for sparsely filled look-up tables is also provided.
Description
The present invention relates to improve the color accuracy of liquid crystal projection apparatus.
Color imaging system is widely used in providing information for spectators.For example, color printer and color copy machine produce the coloured image of hard copy, and television set and computer are promptly producing image usually on cathode ray tube (CRT) on the display.Though CRT is successfully used for many years always, but promoted the exploitation of multiple substitute for the low-power consumption such as being used for portable computer and lightweight display with for the demand of the large area display such as being used for large-screen receiver, described substitute particularly comprises the LCD projecting apparatus.
The color imaging system that accurately and consistently produces the high-quality colour image is needs highly.Unfortunately, it is difficult producing accurate coloured image consistently.What (have peak or level and smooth) color frequency spectrum, the optical element such as prism, polarizer, optical filtering and lens that some problem of restriction color accuracy comprises the light source of only launching finite quantity light, produced by light source made the characteristic of coloured image distortion and decay and only had that limited capability handles infinite range may colored electronic sub-system.
The color accuracy problem is solved in every way.Utilize color printer and color copy machine to print and scanning colour patchery (color patch), with and scanning result be used to produce the look-up table that is used for the compensate for color error.For example, license to the United States Patent (USP) 5 of the title of Balasubramanian for " Iterative Technique for Refining ColorCorrection Look-Up Tables (being used to improve the iterative technique of colour correction look-up table) " on July 15th, 1997,649,072 disclose the iterative technique that RGB (redness-green-blueness) numerical value colourity converts the RGB numerical value of device to.United States Patent (USP) 5,649,072 instruction converts the RGB numerical value of input to printer CMYK (cyan-magenta-yellow-black) value by using look-up table.Look-up table stores is by being input to printer to one group of RGB numerical value (about 1000) and definite numerical value, and it prints corresponding one group colored patchery then.Measurement mechanism is measured the RGB numerical value of the device of each colored patchery then.In order to produce look-up table numerical value, transform processor computational transformation vector, the conversion difference of the interpolation of this vector representative between the RGB numerical value of one group of RGB numerical value of input and device.The conversion vector is used for producing first group look-up table RGB numerical value.Then, in order to verify the accuracy of this table, the RGB numerical value of original input group is applied to this look-up table, and corresponding table output is compared with measurement result.Then, determine how original input group is transformed to the result of measurement and the remainder error between this measurement result itself at look-up table, and this remainder error is used for " correction " look-up table numerical value, and these numerical value are tested by using original input group and measurement result once more.This process repeats, till remainder error is in acceptable limit range.
Though at United States Patent (USP) 5,649, disclosed colour correction technology is useful in color printer and color copy machine in 072, this technology depends on the colored constancy of output inherently.Just, when each specific colourity RGB numerical value is applied to color printer, this printer will produce identical colour, and complete and all images formerly are irrelevant.Particularly, United States Patent (USP) 5,649,072 instructs the process of only using one group of measured value particularly.The look-up table numerical value of colour correction is conditioned, and is passing through until original input RGB numerical value group till the colored patchery of generation measurement after the look-up table conversion.Unfortunately, not every color imaging system all presents colored constancy.Color imaging system does not comprise veneer LCD and LCoS projecting apparatus.
Veneer LCD or LCoS color projecting apparatus move by the light of the different colours that rolls fast and in proper order on single LCD plate modulator, and described different colours is red (R), green (G) and blue (B) typically.The LCD plate modulator is according to the light of being modulated different colours usually by the color video information of frame application, and each frame is made up of the color sub-frame of component, and the light of each different colours has a subframe, promptly red, green and blue subframe.Therefore, the light of each color is modulated in each frame.Unfortunately, do not having under the situation of correction mechanism, the colour that produces in a subframe depends on the image of last subframe.This be considered to the liquid crystal material responses time and the colour that causes by the stray electrical effect between the result that mixes.So, the colour that the content of not knowing to be produced in last subframe just can not calculate to a nicety and produce in subframe.
It is a kind of that to be used to the colour correction mechanism of the prior art of their color accuracies of lacking of veneer LCD color projecting apparatus compensation be to write black in advance before forming each subframe.Writing black in advance forces the LCD material to be in predetermined state before producing in each subframe.Because each subframe is from same initial condition, so the colour that produces in subframe can be calculated to a nicety.Though write the artefact that black successfully solves last subframe in advance, write black in advance and have the very important disadvantages that reduces display brightness.
So, a kind ofly be used for realizing that the new alignment technique of LCD projecting apparatus color accuracy will be useful.A kind ofly be used for realizing LCD projecting apparatus color accuracy and do not reduce the new alignment technique of brightness or even more useful.Particularly, use look-up table to realize that the technology of color accuracy is useful especially.The method that obtains being used for the numerical value of look-up table also is useful, and the numerical value that wherein obtains is used for color accuracy and not be used in each subframe writing black data in advance in the LCD projecting apparatus.Use look-up table to realize that the technology of color accuracy also can be used to the color accuracy that obtains higher degree in conjunction with the method that writes black in advance.
Principle regulation of the present invention is used the color accuracy of look-up table to realize improving in the mode that need not write data in each subframe in advance.And these principles regulation is used for the process of look-up table numerical value of accomplished color accuracy.Principle of the present invention also provides the color accuracy that uses the look-up tables'implementation raising in the LCD projecting apparatus and the colour correction technology that does not reduce brightness.These principles also provide the color accuracy of realization raising and have not be used in the veneer LCD projecting apparatus that writes data in each subframe in advance.
Veneer LCD projecting apparatus according to principle of the present invention comprises a colour correction network, and this colour correction network becomes can compensate three looks (RGB) data of colour correction of the transmission characteristic of LCD projecting apparatus to three looks (the being generally RGB) data conversion of the input that obtains from input signal (such as from computer).Such LCD projecting apparatus also comprises a modulator, is used in response to three looks (RGB) data of colour correction selectively color modulation light beam, so that produce image by the input beam that uses modulation on screen.Preferably, for fear of the luminance loss, veneer LCD projecting apparatus does not write data in advance on each subframe.But use the writing in advance of data on each subframe do not got rid of in the use of colour correction network.
Colour correction network according to principle of the present invention comprises a look-up table, and it is the RGB data of colour correction that this look-up table is assisted the RGB data conversion of input.Equally advantageously, colour correction network implementation insertion technology reduce the input a RGB data conversion be the hardware requirement of the RGB data of colour correction.
Principle of the present invention also stipulates to be used for the process of numerical value of the colour correction that obtains storing in look-up table.According to this process, uncorrected colored numerical value is used for producing its color characteristic and wants measured image, and described color characteristic comprises brightness especially.Then, the colored numerical value of calculation correction so that the brightness of the colored numerical value of proofreading and correct is identical with the brightness that is produced by uncorrected colored numerical value basically, and makes the characteristic of the colored numerical compensation system of proofreading and correct.Use the colored numerical value of proofreading and correct to produce its color characteristic then and want measured image.Then, determine whether produce image about the colored numerical value of proofreading and correct, wherein acceptable brightness is based on the light characteristic by using uncorrected colored numerical value to obtain with acceptable brightness and color characteristic.If do not produce above-mentioned image, then advantageously produce the colored numerical value of one group of new correction by the result who determines before using.This process repeats, till realizing acceptable color characteristic.The colored numerical value that is used for producing the correction of the image with acceptable brightness and color characteristic is stored in the look-up table and in look-up table and is used.Advantageously, the data of colour correction and uncorrected data have the RGB color format.
Should see that above-mentioned in a word bright and following detailed description only is exemplary and explanat.The distortion of other embodiment, embodiment and equivalent and others of the present invention, purpose and advantage will be tangible for those skilled in the art, and can from the research of accompanying drawing, disclosure and appended claims, obtain, maybe can be learnt by putting into practice the present invention.
On figure:
Fig. 1 is the schematic diagram according to the veneer LCD projecting apparatus of principle of the present invention;
Fig. 2 is the flow chart that is used for determining the process of the look-up table numerical value that uses in veneer LCD projecting apparatus shown in Figure 1; And
Fig. 3 is the flow chart of the interpolation process implemented in veneer LCD projecting apparatus shown in Figure 1, be used for the colored numerical value that obtains proofreading and correct from the register space look-up table that reduces.
At length with reference to embodiments of the invention, the example of these embodiment is described on accompanying drawing now.
Fig. 1 schematically illustrates the veneer LCD projecting apparatus 8 that is suitable for implementing principle of the present invention.Should see that 8 expressions of LCD projecting apparatus are to illustrate the unspecific projecting apparatus that the common mode how to benefit of image projection system illustrates from the present invention.
The purposes of LCD projecting apparatus 8 is that the light beam 10 of modulation is projected on the screen 12, so that create according to the image such as the such input signal of the numeral of TV signal, signal that computer generates or other type or analog signal.As shown, input signal is imported into the port one 4 of input system 16.In fact, input signal is applied in (see above) with the form of frame.
LCD projecting apparatus 8 also comprises controller 18, total operation of these controller 18 control projecting apparatus.During initialization, controller 18 is from memory 20 retrieval table data.Controller 18 sends to the colour-compensating network 29 with look-up table 21 to look-up table data via the data/address bus 28 with enable line.Under the control of controller 18, colour-compensating network 29 selectively outputs to Gamma correction network 40 (see above) to the data of colour correction (red, green and blue) during color sub-frame.Therefore, colour-compensating network 29 is implemented red output table 22, green output table 24 and blue output table 26 effectively.Because look-up table numerical value is important, will make an explanation in more detail in the back so determine the process of these numerical value.In addition, in order to reduce the size of look-up table 21, colour-compensating network 29 is implemented interpolation process, and this also discusses in the back.
Controller 18 is also controlled total operation of input system 16, light source 30, modulator 41 (typically, LCD plate) and Gamma correction network 40.Input system 16 is transformed into 8 bit color picture signal R to the data-signal (such as TV signal) that enters on port one 4
IN, G
INAnd B
IN, the coloured image that these picture signal representatives will produce in a specific frame.These signals are imported into colour-compensating network 29.According to the look-up table data from memory 20, colour-compensating network 29 is R
INBe transformed into RED (redness) data of the correction on the bus 34, G
INBe transformed into GREEN (green) data of the correction on the bus 36, and B
INBe transformed into BLUE (blueness) data of the correction on the bus 38.
Because color data is organized in following discussion more, for clarity, importantly distinguish various groups.So the color data group that is added to colour-compensating network 29 will be called as R
ING
INB
INData, and will be called as R ' G ' B ' data from the color data group of colour-compensating network 29.Other color data group is introduced afterwards.
Still with reference to figure 1, R ' G ' B data (on bus 34,36 and 38) are added to Gamma correction network 40.Gamma correction network 40 comprises look-up table or R ' G ' B data is carried out Gamma correction to produce R
g' G
g' B
g' table of data, wherein the g subscript is represented the information of Gamma correction.R
g' G
g' B
g' data are added to modulator 41 via bus 49.
Controller 18 control light sources 30, like this, red light R, green light G, blue light B sequentially are added to modulator 41.In first color sub-frame, red light R is added to modulator 41, and this modulator is according to R
g' data-modulated red light R to be to produce the light beam 10 of modulation.The light beam 10 of modulation is by optical system 48, and this optical system scans the light beam 10 of modulation on screen 12.In next color sub-frame, green light G is added to modulator 41, and this modulator is according to G
g' data-modulated green light G to be to produce the light beam 10 of modulation.In next color sub-frame, blue light B is added to modulator 41, and this modulator is according to B
g' data-modulated blue light B to be to produce the light beam 10 of modulation.By switching fast between redness, green and blueness, the observer sees full-colour image on screen 12.
As previously mentioned, determine that the look-up table numerical value in order to produce R ' G ' B ' data is important.Each LCD projecting apparatus 8 has relevant colour gamut, and promptly the LCD projecting apparatus can be by the scope of the colour that the colourama 10 of superposition modulated produces on screen 12.Colour can be described quantitatively and be measured by the group of using three numerical value, for example uses three colour cells (X, Y, Z) { typically RGB} or (L, u ', v ') organize, wherein L is for the brightness of colour, and u ' and v ' lump together according to color saturation and tone and reflect colored point.Each three primary colors group can be transformed into other group by using mathematic(al) manipulation.For convenience's sake, will utilize (L, u ', v ') group below, mainly be because the aberration in (L, u ', v ') group is approaching corresponding to the aberration of being felt.Aspect color accuracy, the Euclidean distance in (u '-the v ') space of realizing that the uniform equivalence closely between two kinds of colours is colored in making minimizes.On mathematics, realize that uniform equivalence closely between two kinds of colours is in making chromatism measurement value Δ C minimize:
ΔC＝sqrt{(u
1-u
2)
2+(v
1-v
2)
2}
(u wherein
1, v
1) and (u
2, v
2) be (u ', v ') component of the colour of two unanimities.0.015 or littler Δ C to be considered to usually use for the user be enough.
Given color group R from input system 16
ING
INB
INNumerical value according to storage in look-up table 21 is transformed R ' G ' B ' data.These data (behind Gamma correction) are modulated at redness, green and the blue light of imaging on the screen 21.Screen picture is characterised in that specific colored numerical value tlv triple (L, u ', v ').If display is desirable display, if the melange effect between colour promptly do not occur, then LCD projecting apparatus 8 will produce (L, u ', v ') numerical value, and this numerical value only depends on (L, u ', the v ') numerical value of three primary colors point and some transmission characteristic of system.Theoretical value will be represented as (L
t, u
t', v
t'), t subscript representation theory value wherein.Yet, if R
ING
INB
INData are applied directly to Gamma correction network 40, and then screen 12 has generation the image of (L, u ', v ') combination different with theory.Work as R
ING
INB
IN(L, u ', v ') combination that data finally obtain when directly being used will be represented as (the L of measurement
m, u
m', v
m') numerical value.
In LCD projecting apparatus 8, colour-compensating network 29 is R
ING
INB
INBe transformed to R ' G ' B ', like this, Δ C 0.015 and 0.02 Δ L/L
mAdvantageously obtain (L, u ', v ') combination in the tolerance of (promptly being not more than 2% luminance errors), wherein L=L
m, u '=u
t' and v '=v
t'.Therefore, colour-compensating network 29 is proofreaied and correct its input data, so that ought and directly use R
ING
INB
INWhen comparing, almost do not have the luminance loss, also produce high color accuracy simultaneously in the mode that realizes color accuracy.
The process that is used for calculating R ' G ' B numerical value in fact is an iteration, and makes an explanation by means of Fig. 2.Suppose before carrying out this process, to have determined the gamma correction table in the projecting apparatus.Gamma correction table guarantees that gray-scale information correctly reproduces according to power time rule (power-law) function (typically, time rule/gamma of the power between 2.2 and 2.5).Power time rule function is associated the gray-scale data that is input to projecting apparatus with the light of being exported for each color channel by projecting apparatus.This process 200 begins in step 202, and in step 204, with one group of (uncorrected) R
ING
INB
INLook-up table 21 is loaded in input.In step 206, these R
ING
INB
INInput is used to produce coloured image (image of each subframe) then, and the image that finally obtains is carried out colour measure, with (the L that obtains measuring
m, u
m', v
m') numerical value.Then, in step 208, use theoretical value (L
t, u
t', v
t'), measured value (L
m, u
m', v
m') and the nonlinear transfer function of LCD projecting apparatus 8 produce the one group of R that is loaded onto in the look-up table 21 " G " B " numerical value.The subscript of two left-falling strokes is used for representing the group of the centre of colored numerical value.Should be pointed out that for each R
ING
INB
INInput, object brightness L
mWith the colored point of theory (u
t', v
t') be used to determine R " G " B " group.Just, brightness is fixed.
Then, in step 210, by using R " G " B " group, get new colored measured value and obtain for R " G " B " (L, u ', v ') numerical value of group.In step 212, calculate then to find at (L
m, u
t', v
t') difference between numerical value and (L, u ', v ') numerical value, whether can accept (face as follows) to determine (L, u ', v ') numerical value.If unacceptable, then this process turns back to step 208, so that calculate and load another R " G " B " group.Then in step 210, R " G " B " group is used to obtain new (L, u ', v ') numerical value, and in step 212, at (L
m, u
t', v
t') difference between numerical value and (L, u ', v ') numerical value is used to determine whether (L, u ', v ') numerical value can be accepted now.Proceed iteration, until Δ C and Δ L/L
mBe lower than respectively till 0.015 and 0.02.Advantageously, at (L
m, u
t', v
t') difference between numerical value and (L, u ', v ') numerical value is used to calibrate from once iterating to the step-length of next iteration.In case reach acceptable numerical value, just in step 214 R " G " B " group be stored in memory 20 (see figure 1)s with as R ' G ' B ' group for use in the future.In step 216, stop this process 200 then.
Importantly, the brightness that finally obtains when using R ' G ' B ' group is L
mOr very near L
mAnd, though the brightness when each iteration remains the numerical value L that originally obtained
mOr near the numerical value L that originally obtained
m, but when iteration finished, the numerical value of L, u ', v ' should be respectively the L that satisfies Δ C and Δ L criterion
m, u
t', v
t'.
Though above method is favourable, in fact directly enforcement may be high cost.In order to understand this point, consider to use 8 bit R
IN, G
INAnd B
INNumerical value.This will need to adopt (or a plurality of) look-up table of the costliness with 24 bit Input Address of 16777216 registers.So, replacing using 24 complete bit Input Address look-up tables, colour-compensating network 29 uses the look-up table 21 of sparse filling and implements to make up by rights the interpolation process of look-up table numerical value.Fig. 3 illustrates suitable interpolation process 300, is used for determining when use has the look-up table 21 of limited register space suitable R ' G ' B ' output.
This process 300 begins in step 302, and in step 304, obtains RGB numerical value (see figure 1) from input system 16.In step 306, colour-compensating network 29 is determined resulting R then
ING
INB
INNumerical value in look-up table 21 whether by Direct Transform.If then colour-compensating network 29 is exported the R ' G ' B ' numerical value of Direct Transform in step 308, and in step 310, stops this process 300.
Yet, if the R that obtains
ING
INB
INNot by Direct Transform, then colour-compensating network 29 is found out (a) the most approaching resulting R to numerical value in step 312 in look-up table 21
ING
INB
INNumerical value and in look-up table 21 by the R of Direct Transform
ING
INB
INNumerical value (these R
ING
INB
INNumerical value is called as immediate neighbor later on), and (b) this immediate neighbor from the R that obtains
ING
INB
INThe color space Euclidean distance of numerical value.This Euclidean distance is measured in (L, u ', v ') space, because the colour errors criterion is stipulated in this space.In step 314, colour-compensating network 29 uses these immediate neighbors and distance to calculate the R ' G ' B ' numerical value of interpolation then.Resulting R
ING
INB
INInput is approaching more with specific neighbor, and the R ' G ' B ' output of interpolation is approaching more with the relevant R ' G ' B ' numerical value of neighbor.In step 316, in case the R ' G ' B ' numerical value of interpolation is calculated, then the numerical value of this interpolation just is used afterwards.At last, in step 310, stop this process 300.Interpolation process 300 usefulness are implemented compared with the hardware of the needed much less of look-up table of 16777216 registers.The distortion of interpolation process comprises the interpolation of the nonlinear combination of using immediate neighbor more than two and the R ' G ' B ' numerical value by using these neighbors.
The process of the color accuracy that is used to be improved also can advantageously be used for revising the colour gamut of display.If for each RinGinBin numerical value, (the L that wants, u ', v ') numerical value is not based on the primary colours of actual display, think highly of some existing other primary colours (we call target color gamut to it) and be based on to be shown, then the look-up table determined of the process by previous general introduction will provide the conversion of colour gamut from the colour gamut of display itself to target color gamut, and the artefact that mixes between the while compensate for color.
Here the embodiment of Chan Shuing is used for illustrating the present invention and actual application thereof, so that make those skilled in the art can utilize the present invention.Other distortion of the present invention and correction will be conspicuous for those skilled in the art.So scope of the present invention is planned by the appended claims regulation, thereby provide whole understanding scopes to the equivalent of all aspects.
Claims (19)
1. the method for definite colour correction numerical value comprises:
(a) use one group of uncorrected numerical value on display, to produce image;
(b) the colored parameter of measurement image of generation in step (a);
(c) obtain the light characteristic of image from the colored parameter of step (b), measuring;
(d) calculate one group of numerical value of proofreading and correct, so that the light characteristic of numerical value that should group correction is substantially equal to the light characteristic that obtains in step (c);
(e) use the numerical value of this group correction of in step (d), calculating on display, to produce image;
(f) the colored parameter of measurement image of generation in step (e);
(h) determine from the measured value of step (f) whether the image that produces is in the acceptable level of brightness and color characteristic step (e), wherein the acceptable level of brightness is based on the light characteristic that obtains in the step (c), and wherein acceptable color characteristic is based on theoretical colored numerical value group; And
(i) repeat step (d) to (h), till this group correction numerical value that calculates produces acceptable luminance level and acceptable color characteristic in step (d).
2. the method for the colored numerical value of proofreading and correct according to the generation of claim 1, the numerical value group of wherein uncorrected numerical value group and correction is RGB (red, green and blue) data.
3. the method for the colored numerical value of proofreading and correct according to the generation of claim 1, wherein step (d) comprises the error between the colored parameter of light characteristic that use obtains and measurement in step (f) in step (c).
4. the method for the colored numerical value of proofreading and correct according to the generation of claim 3, wherein step (d) also comprises the error between the colored parameter on the colored numerical value group of colored parameter that use is measured and theory in step (f).
5. the method for the colored numerical value of proofreading and correct according to the generation of claim 1, wherein Li Lun colored numerical value group is based on the mathematical relationship between the colored parameter of uncorrected numerical value and measurement.
6. method that realizes color accuracy in the LCD display may further comprise the steps:
(a) use one group of uncorrected RGB data (RinGinBin) on LCD display, to produce image;
(b) color characteristic of measurement image of generation in step (a);
(c) obtain the light characteristic of image from the color characteristic of step (b), measuring;
(d) calculate one group of RGB numerical value of proofreading and correct, so that the light characteristic of RGB numerical value that should group correction is substantially equal to the light characteristic that obtains in step (c);
(e) use the RGB numerical value of this group correction of in step (d), calculating on display, to produce image;
(f) the colored parameter of measurement image of generation in step (e);
(g) determine from the measured value of step (f) whether the image that produces is in the acceptable level of brightness and color characteristic step (e), wherein the acceptable level of brightness is based on the light characteristic that obtains in the step (c), and wherein acceptable color characteristic is based on theoretical colored numerical value group;
(h) repeat step (d) to (g), till the RGB numerical value of proofreading and correct produces acceptable luminance level and acceptable color characteristic; And
(i) the RGB numerical value group of the correction of storage acceptable luminance level of generation and acceptable color characteristic is for using in the future.
7. the method for claim 6, wherein step (d) comprises the error between colored parameter that use is measured and the theoretical colored numerical value group in step (f).
8. veneer LCD projecting apparatus comprises:
Being used for the RGB data conversion of input is the colour correction network of the RGB data of colour correction;
Be used for selectively modulating the modulator of the light of input in response to the RGB data of colour correction;
Be used for redness, green and blue light selectively are input to the light source of modulator;
Be used for the RGB data of input are applied to the input system of colour correction network; And
Be used to use the light beam of modulation on screen, to produce the imaging system of image;
Wherein the colour correction network produces the RGB data of colour correction, the RGB data of this colour correction produce image so that image has basically and directly uses brightness identical when importing the RGB data, and the non-linear colored transfer function of RGB compensation data veneer LCD projecting apparatus that makes colour correction.
9. according to the veneer LCD projecting apparatus of claim 8, wherein input system produces uncorrected RGB data from the data-signal that enters.
10. according to the veneer LCD projecting apparatus of claim 8, wherein the colour-compensating network comprises look-up table.
11. according to the veneer LCD projecting apparatus of claim 10, wherein look-up table keeps the RGB data of the colour correction that obtains by following steps:
(a) use one group of uncorrected RGB data (RinGinBin) on screen, to produce image;
(b) color characteristic of measurement image of generation in step (a);
(c) obtain the brightness of image from the color characteristic of step (b), measuring;
(d) calculate one group of RGB numerical value of proofreading and correct, so that the brightness of RGB numerical value that should group correction is substantially equal to the brightness that obtains in step (c);
(e) use the RGB numerical value of this group correction of in step (d), calculating on screen, to produce image;
(f) the colored parameter of measurement image of generation in step (e);
(g) determine from the measured value of step (f) whether the image that produces has acceptable brightness and color characteristic step (e), wherein acceptable brightness is based on the brightness that obtains in the step (c), and wherein acceptable color characteristic is based on theoretical colored numerical value group;
(h) repeat step (d) to (g), till finding the one group of RGB numerical value proofreaied and correct that produces acceptable luminance level and acceptable color characteristic; And
(i) RGB value storage that this group that produces acceptable luminance level and acceptable color characteristic is proofreaied and correct is at look-up table.
12. the veneer LCD projecting apparatus of claim 11, the wherein error between the colored parameter on the colored numerical value group of the colored parameter of step (d) use measurement in step (f) and theory.
13. according to the veneer LCD projecting apparatus of claim 10, wherein the colour correction network implementation is sought the interpolation process of the RGB numerical value of proofreading and correct.
14. according to the veneer LCD projecting apparatus of claim 13, wherein the interpolation processor moves by following steps:
(a) obtain uncorrected RGB data;
(b) determine that whether uncorrected RGB data are directly converted to the RGB numerical value of correction by look-up table;
(c) if uncorrected RGB data by Direct Transform, are then exported the RGB numerical value of Direct Transform;
(d), then determine the immediate neighbor of uncorrected RGB data if uncorrected RGB data are not directly converted to the RGB numerical value of correction by look-up table;
(e) use the RGB numerical value of the correction relevant to come the RGB numerical value of interpolation correction with this immediate neighbor; And
(f) if uncorrected RGB data not by Direct Transform, are then exported the RGB numerical value of the correction of interpolation.
15. according to the veneer LCD projecting apparatus of claim 14, wherein the interpolation processor comes the RGB numerical value of interpolation correction according to the distance between each immediate neighbor and uncorrected RGB data.
16. according to the veneer LCD projecting apparatus of claim 14, wherein look-up table keeps the RGB data of the colour correction that obtains by following steps:
(a) use one group of uncorrected RGB data (RinGinBin) on screen, to produce image;
(b) color characteristic of measurement image of generation in step (a);
(c) obtain the brightness of image from the color characteristic of step (b), measuring;
(d) calculate one group of RGB numerical value of proofreading and correct, so that the brightness of RGB numerical value that should group correction is substantially equal to the brightness that obtains in step (c);
(e) use the one group of RGB numerical value proofreaied and correct that in step (d), calculates on screen, to produce image;
(f) the colored parameter of measurement image of generation in step (e);
(g) determine from the measured value of step (f) whether the image that produces has acceptable brightness and color characteristic step (e), wherein acceptable brightness is based on the brightness that obtains in the step (c), and wherein acceptable color characteristic is based on theoretical colored numerical value group;
(h) repeat step (d) to (g), till finding the one group of RGB numerical value proofreaied and correct that produces acceptable luminance level and acceptable color characteristic; And
(i) RGB value storage that this group that produces acceptable luminance level and acceptable color characteristic is proofreaied and correct is at look-up table.
17., also comprise the controller of control colour correction network, modulator, light source and input system according to the veneer LCD projecting apparatus of claim 8.
18., wherein import the RGB data and be employed by frame according to the veneer LCD projecting apparatus of claim 8.
19. according to the veneer LCD projecting apparatus of claim 19, wherein modulator comprises the LCD plate.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US46603903P | 2003-04-28 | 2003-04-28 | |
| US60/466,039 | 2003-04-28 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN1781318A true CN1781318A (en) | 2006-05-31 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNA2004800113305A Pending CN1781318A (en) | 2003-04-28 | 2004-04-14 | Liquid crystal projector having increased color accuracy |
Country Status (6)
| Country | Link |
|---|---|
| EP (1) | EP1621023A1 (en) |
| JP (1) | JP2006526910A (en) |
| KR (1) | KR20060004687A (en) |
| CN (1) | CN1781318A (en) |
| TW (1) | TW200508773A (en) |
| WO (1) | WO2004098201A1 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| US7065628B2 (en) | 2002-05-29 | 2006-06-20 | Intel Corporation | Increasing memory access efficiency for packet applications |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH05127620A (en) * | 1991-11-06 | 1993-05-25 | Matsushita Electric Ind Co Ltd | Method and circuit for adjusting liquid crystal projection type color display |
| DE69315285T2 (en) * | 1992-09-02 | 1998-05-28 | Matsushita Electric Ind Co Ltd | Device for processing an image signal |
| FR2731124B1 (en) * | 1995-02-27 | 1997-04-04 | Thomson Consumer Electronics | MONOVALVE COLOR PROJECTION SYSTEM |
| US5649072A (en) * | 1995-06-07 | 1997-07-15 | Xerox Corporation | Iterative technique for refining color correction look-up tables |
| JP3568367B2 (en) * | 1997-07-08 | 2004-09-22 | パイオニア株式会社 | Display device |
| US6611249B1 (en) * | 1998-07-22 | 2003-08-26 | Silicon Graphics, Inc. | System and method for providing a wide aspect ratio flat panel display monitor independent white-balance adjustment and gamma correction capabilities |
| US7595811B2 (en) * | 2001-07-26 | 2009-09-29 | Seiko Epson Corporation | Environment-complaint image display system, projector, and program |
-
2004
- 2004-04-14 WO PCT/IB2004/001225 patent/WO2004098201A1/en not_active Application Discontinuation
- 2004-04-14 EP EP04727342A patent/EP1621023A1/en not_active Withdrawn
- 2004-04-14 KR KR1020057020402A patent/KR20060004687A/en not_active Application Discontinuation
- 2004-04-14 JP JP2006506507A patent/JP2006526910A/en active Pending
- 2004-04-14 CN CNA2004800113305A patent/CN1781318A/en active Pending
- 2004-04-23 TW TW093111504A patent/TW200508773A/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| EP1621023A1 (en) | 2006-02-01 |
| TW200508773A (en) | 2005-03-01 |
| WO2004098201A1 (en) | 2004-11-11 |
| KR20060004687A (en) | 2006-01-12 |
| JP2006526910A (en) | 2006-11-24 |
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