MXPA99005920A - Device and method for auto adjustment of image condition in panta - Google Patents

Abstract

The present invention relates to: A device and method for automatically adjusting an image condition on a screen are presented. The device and method of the present invention optimize the image condition of a screen in accordance with individual preferences taking into account the brightness and color temperature initially set by a user. Particularly, the present invention includes a photo sensor for detecting ambient illumination and a micro processor that uses the detected data to appropriately adjust the image condition in relation to a user preference.

Description

DEVICE AND METHOD FOR SELF ADJUSTMENT OF IMAGE CONDITION ON DISPLAY BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to display devices, and more particularly to a device and method for automatically adjusting the conditions of the image on a screen. The present invention automatically adjusts the condition of the image with consideration of a condition initially set by the user when the brightness around the screen and the color temperature vary. BACKGROUND OF THE RELATED ART Constant developments of technologies have been made for the automatic adjustment of a deployed image to provide a better and more convenient environment for the user. The technology for automatically adjusting the condition of the image is applied to displays such as a television (TV) or a computer monitor, and can be implemented in several ways. For such displays, the conditions of the image in terms of brightness, contrast and color temperature can be adjusted automatically according to the ambient luminance and the color temperature using a pre-set search table.

The search table is established by experimentally obtaining the conditions of the image, this being contrast and brightness with respect to detected color signal outputs of ambient color temperature and luminance at the time, and color brightness and color temperature signals theoretical The search table is stored in a memory, and according to a detected ambient luminance and color temperature, a contrast and brightness of the image are adjusted based on the detected color and environment signals. Generally, a TV is viewed from a distance by the user during the afternoon after sundown and under lighting, while a computer monitor is viewed by the user from a nearby distance during the day in an office. Therefore, the image conditions for the TV and the monitor are different. Also, a slightly poor focus and resolution does not greatly affect the observation of TV because moving images are displayed. However, focus and resolution affect the observation of a monitor because most of the work on the monitor is carried out by viewing a still image such as a text or a graphic. Therefore, the image condition required for the monitor varies, depending on the job. Although an image condition is adjusted to an optimal condition for environmental brightness and color temperature, because the adjustment is made using a lookup table, a high quality image can not be provided. In particular, the adjustment is made automatically according to pre-set data without any consideration to the user's preferences or fixed values, which results in differences between the adjusted values and the current environmental conditions. COMPENDIUM OF THE INVENTION For example, an object of the present invention is to solve at least the problems and disadvantages of the related art. An object of the present invention is to provide a device and a method for automatically adjusting the image conditions by enabling an optimal image condition on a screen allowing an optimal image condition regardless of the changing ambient luminance conditions. Advantages, objects, and additional features of the invention will be set forth in part in the description which is noted below and in part will be apparent to those of ordinary skill in the art in examining the following or may be learned by practice of the invention. The objects and advantages of the invention can be realized and obtained as is particularly pointed out in the appended Claims. To achieve the objects and in accordance with the purposes of the invention, as they are incorporated and widely described therein, a device for automatically adjusting an image condition of a screen includes a color signal detecting unit that detects a signal from color of an environmental luminance around the screen; a recognition unit that processes the color signal of the ambient luminance detected by the color signal detector unit that recognizes ambient brightness and ambient color temperature of the screen; a unit that stores a brightness, a contrast and a color temperature of an image set by a user, and the environmental brightness and ambient color temperature of the screen recognized by the recognition unit; a comparison unit that calculates an average of the environmental brightness and the ambient color temperature of the screen during a predetermined period, and comparing the average data with the reference data of the ambient brightness and the ambient color temperature of the stored screen in the storage unit to obtain variations of the calculated average data; and a control unit that stores the ambient brightness and ambient color temperature recognized by the recognition unit as the reference data when the user selects an automatic adjustment mode, and reflecting the respective variations in the brightness and temperature of the color calculated by the unit of comparison with the brightness, contrast and color temperature of the image set by the user, thereby adjusting an image condition. In the preferred embodiment, the color signal detector unit may be a sensor image providing two outputs of Cyan and yellow. Also, the recognition unit recognizes a Cyan and yellow sum of the color signal detector unit as the environmental brightness of the screen and a Cyan to yellow ratio of the color signal detector unit as the environmental color temperature of the screen. A method for automatically adjusting the image conditions of a screen according to the present invention includes (1) storing a brightness and a color temperature of an image set by the user; (2) determining the execution of an automatic adjustment mode in which the brightness, the contrast and the color temperature of the image are adjusted automatically according to a variation of the environmental brightness; (3) When determining an execution of the automatic adjustment mode in (2), detecting the environmental brightness and the color temperature, store the environmental brightness and the color temperature as the reference data of the environmental brightness and the color temperature , and calculate the average data on environmental brightness and color temperature during a predetermined period; (4) compare the average data of the environmental brightness and the color temperature calculated in (3) for the reference data on the environmental brightness and the color temperature, and calculate the respective variations, and (5) reflect the respective variations calculated in (4) to the brightness, contrast and color temperature set by the user in (1), to adjust the condition of the image. The execution of the automatic adjustment mode in (2) includes an execution of the automatic adjustment mode in which the brightness and the contrast of the image are adjusted, and an execution of an automatic mode of adjustment in which the color temperature of the image is adjusted, where the user is allowed to select at least one of the automatic adjustment modes. Also, the reflection in (5) further includes the step of gradually adjusting the condition of the image by taking an intermediate linear value when a difference of value set by the user and a value at which the relative variation is reflected that is above a preset level . BRIEF DESCRIPTION OF THE DRAWINGS The invention will be described in detail with reference to the following drawings in which similar reference numbers refer to similar elements where: Figure 1 is a block diagram showing a device for automatically adjusting a condition of image of a screen according to the present invention; Figure 2 is a block diagram showing a device for automatically adjusting an image condition of a computer monitor according to the present invention; and Figure 3 is a flowchart showing a method for automatically adjusting an image condition of a computer monitor in accordance with the present invention. Figure 4 is a diagram of a microprocessor in Figure 2. DETAILED DESCRIPTION OF THE PREFERRED MODALITY Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Figure 1 shows a device for automatically adjusting an image condition of a screen according to the present invention including a detector unit 11 for detecting environmental brightness and color temperature, and taking out the detected data; a video processor 12 that receives and digitizes the output signals of the detector unit 11 to obtain the environmental brightness and color temperature around the screen, and adjust the brightness, contrast and color temperature of an image using the data obtained in consideration of the brightness, contrast and color temperature selected by a user, and a display unit 13 for presenting the adjusted image on a screen. In the preferred embodiment, the detector unit 11 is a photo sensor and the video processor 12 includes a micro processor. Also, the video processor 12 automatically adjusts the image for presentation, on a TV or computer monitor for example, according to the output signals of the photo sensor using a relative variation of brightness, contrast and color temperature in combination with the brightness, contrast and color temperature initially set by a user according to the user's preferences. Figure 2 shows a device for automatically adjusting an image condition of a computer monitor according to the present invention including a detector unit 21 which detects an environmental brightness and a color temperature, and outputs the detected data; a microprocessor 22 that receives and digitizes the output signals from the detector unit 21 to obtain the environmental brightness and color temperature around the monitor, and outputs control signals to adjust the brightness, contrast and color temperature of an image using the data obtained in consideration of the contrast brightness and color temperature selected by a user; u pre video amplifier 24 which amplifies a video signal for adjusting the image according to the control of the microprocessor 22; a video output unit 25 that processes the adjusted image for display; and a color display tube (CDT) 26 showing the adjusted image.As in the detector unit 11 of Figure 1, the detector unit 21 is a sensor photo 21a in the preferred embodiment that outputs the detected data by two electrical signals such as Cyan (Cy) and yellow (Ye). The Cyan Cy is sensitive to blue and the yellow Ye is sensitive to red, the output signals Cy and Ye are processed through an analog-to-digital converter in a video processor such as the microprocessor 22, to determine the brightness and color temperature around the monitor. Particularly, the environmental brightness is obtained as a sum of the outputs (Cy + Ye) of the photo sensor 21a, using the sensitivity of cyan (Cy to the blue light and the sensitivity of yellow Ye to the red light.) Similarly, the temperature of environmental color is obtained as a ratio of cyan Cy to yellow YE (Cy / Ye). Generally, when the light of an incandescent bulb or an incandescent bulb and a fluorescent lamp are present in the environment, an output of cyan Cy is less than the output of yellow Ye. However, when light mainly from an incandescent lamp is present in the environment, the output of cyan Cy is equal to or greater than the output of yellow Ye. In addition, when natural light is mainly present, the output of cyan Cy is greater than the output of yellow Ye.

Using the various reactions of cyan and yellow to light, the sum (Cy + Ye) and the ratio (Cy / Ye) of cyan Cy and yellow Ye can be used as the environmental brightness and the ambient color temperature, respectively. In the preferred embodiment of a device for automatically adjusting an image condition of a TV, the detector unit is also a photo sensor as described with reference to Figure 2 and the signals Cy and Ye are processed through an analog converter to digital in a video processor such as the microprocessor 22, to determine the brightness and color temperature around the monitor and adjust the brightness, contrast and color temperature of an image in consideration of brightness, contrast and temperature of color selected by a user. The image with the adjusted condition is processed similarly as the image for the CDT and is displayed on a TV screen. A method for automatically adjusting an image condition on a screen will be explained with reference to Figure 3. Figure 3 illustrates a flow chart for automatically adjusting an image condition of a screen according to the present invention. Generally, different users have different preferences to see a screen, and initially set the brightness, contrast and color temperature of the screen. Therefore, when a user sets a brightness, contrast and color temperature of an image in the manual adjustment mode, the microprocessor 22 stores the brightness Bu, the contrast Cu and the color temperature Tu of the image set by the user. in the storage unit (step S31). A determination is made if the user has selected a self-regulating mode (step S32), and if selected, environmental brightness reference data S0 and color temperature reference data R0 are set (step S33). To select the self-regulation mode, the brightness, the contrast and the color temperature of the image are regulated automatically to maintain a level equivalent to the preference set by the user, when the lighting of the surrounding environment changes. Therefore, the user can see a consistent image with a condition initially set according to the user's preference, even if the lighting changes in the surrounding environment. It should be noted that the preference set by the user would be the screen preference setting if the user does not manually adjust brightness, contrast and color temperature.

An explanation of how an image condition is regulated using cyan Cy and yellow Ye will be given with reference to the equation below.

S0 = Cy0 + Ye0 (la) Ro = Cy0 / Ye0 (Ib) As expressed in equations (la) and (Ib), a reference datum of environmental brightness S0 is set as a sum of cyan Cy and yellow Ye received from the detector unit 21, and an environmental color temperature reference data. R0 is set as the ratio Cy / Ye from cyan Cy to yellow Ye received from the detector unit 21.

Sa = S / n (2a) Ra = R / n (2b) Where S = Si + S2 + S3 ... + Sn_? + Sn, Sn = Cyn + Yen, and R = Ri + R2 + R3 ,. «. + Rn-? + Rn, Rn = Cyn / Yen. Using equations (2a) and (2b), the average of the environmental brightness Sa and the average of the environmental color temperature Ra are obtained from the output of cyan Cy and the yellow Ye of the detector unit 1, during a period of predetermined time (step S34). Sd = S0 - Sa (3a) Rd = R0 - Ra (3b) After obtaining the average values of the environmental brightness and the ambient color temperature, Sa and Ra are compared with the reference data S0 and R0 respectively, as shows in equations (3a) and (3b). The results of the comparison are used in equations (4a) to (4c) below to determine the relative amounts of adjustment necessary in the image condition, with respect to the user preference (step S36).

Sd deltaB = X () (4a) deltaV, s Sd deltaC = W () (4b) deltaV8 Rd deltaR »Y () (4c) deltaVr In equation 4, deltaB, deltaC and deltaR are the relative amounts of adjustment or relative variations for the image condition. In equation (4b), || Vs is a value of the variation in environmental brightness, this being the sum of Cy + Ye obtained from the output of photo sensor 21a, when the illumination of the surrounding environment changes by a preset level . In the preferred mode, deltaVs is the variation when the lighting changes by 50 Lux. The value deltaVs is predetermined and stored in the storage unit within the micro processor 22. In equations (4a) and (4c), deltaVr is a value of the variation of the color temperature of the environmental brightness, this being Cy / Ye obtained from the output of the sensor photo 21a, when the color temperature in the surrounding environment changes by a predetermined level. In the preferred embodiment, deltaVr is the variation when the color temperature changes by 3000 K. The value of deltaVr is similarly predetermined and stored in the storage unit within the microprocessor 22. Also, deltaVr may be stored in the same unit of storage. storage or in a different deltaVs and both deltaVr and deltaVs may be stored in the same storage unit or in a different one of Bu, Cu and Tu in step S31. The coefficients X, W and Y are predetermined values representing the adjustment amounts made by a typical user in the brightness, contrast and color temperature of an image, respectively, when ambient illumination and color temperature vary. For example, if the typical user sets the initial contrast to 85 in ambient lighting of 200 Lux, but adjusts the contrast to 95 when the ambience is brighter at 300 Lux and adjusts the contrast to 80 when the ambience becomes darker at 150 Lux, the variation of the contrast for each 50 Lux is 5, this being = 5. The X and Y coefficients can be obtained in a similar way by determining the brightness and color temperature preferred by a typical user by varying the brightness and the color temperature, respectively. In addition, if one or more objects, such as furniture or plants, are close to the sensor photo 21a during the calculations of the relative variations, the two outputs Cy and Ye of the photo sensor 21a may vary slightly depending on the material and color of the object regardless of the actual variation of ambient lighting. Therefore, the effects of the placement of objects, although minimal, can be taken into consideration during the determination of the coefficients X, W and Z varying the placement of different objects, as a variable, with respect to the photo sensor 21a before obtaining X, W and Z. In the preferred embodiment, the coefficients X = 3, W = 5 and Y = 1000. A Once the relative variations of the B, delta C and delta R are obtained through the process above, the level of adjustment for an optimal condition of the image with respect to brightness, contrast and color temperature are determined by equations (5a) a (5c) below (step S37). B = Bu + deltaB (5a) C = Cu + deltaC (5b) T = Tu + deltaR (5c) In equation 5, B is a brightness of the image after completing an image condition adjustment, C is a contrast after completing an image condition adjustment and T is a color temperature of the image completing an image condition adjustment. Because the brightness, contrast and color temperature are adjusted in consideration of the individual preferences of the user using the relative variations deltaB, deltaC and deltat, an optimal image can be obtained for each individual. As indicated above, a micro processor determines the brightness t the color temperature around the monitor and to adjust the brightness, contrast and color temperature of an image in consideration of the selected brightness, contrast and color temperature. by a user. Particularly, Figure 4 shows a flow chart of a micro processor including a storage unit 41 storing the environmental reference brightness S0 and the color temperature R0; a detection unit 43 determines the brightness and color temperature around the monitor as (Cy + Ye) and (Cy / Ye) respectively; a comparison unit 45 calculates an average brightness Sa and a color temperature Ra in the environment for a predetermined period of time according to equation 2, and compares Sa and Ra with S0 and R0 of the storage unit according to the equation 3; and a control unit 47 determines the relative variations of the B, delta C and delta R using the compared values Sd and Rd in accordance with equation 4, taking control signals to adjust the image by the calculated relative variations deltaB, deltaC and deltaR and Bu, Cu and Tu stored in the storage unit, respectively, according to equation 5. Therefore, in the present device and method to automatically adjust an image condition, the brightness Bu, the contrast Cu and the color temperature Tu entered by a user are stored; the average values Sa and Ra are compared with the reference values S0 and R0, of the environmental brightness and color temperature, respectively, to calculate the difference Sd and Rd according to equations (3a) and (3b). The calculated differences Sd and Rd are used to calculate the relative variations of the B, delta C and delta R of the brightness, contrast and color temperature according to equations (4a) to (4c). Finally, the image is adjusted by the amount of relative variations in addition to brightness Bu, contrast Cu and color temperature Tu stored. Also, abrupt or abrupt changes in the brightness and color temperature of the image, which occur when the average data of a predetermined period differ greatly from the values set by the user, can cause fatigue in the user's eyes. As a result, the brightness, contrast and color temperature of the image are gradually increased or decreased during the adjustment of the image condition in the preferred embodiment. In addition, a user may only want an automatic adjustment of brightness and contrast or an automatic adjustment of the color temperature. For example, an automatic adjustment mode for the brightness and contrast of the image, and an automatic adjustment mode for the color temperature can be provided separately for user selection.

As noted above, the device and method for automatically adjusting the image condition of a screen according to the present invention facilitates an automatic adjustment of an image, taking into consideration a variation which may occur due to brightness, contrast and temperature of the image. color initially set by a user. Therefore, the present invention provides an optimum image condition preferred by an individual user with respect to brightness and ambient color temperature. The present device and method for automatically adjusting the condition of the image on the screen especially provides an optimal image condition desired by individual users when the present invention is applied to a TV or a computer monitor, requiring different image conditions depending on the environment of use. The above embodiments are merely illustrative and should not be considered as limiting the present invention. The present instructions can be easily applied to other types of devices. The description of the present invention is intended to be illustrative only, and not to limit the scope of the claims. Many alternatives, modifications and variations will be apparent to those experts in the field

Claims (16)

1. CLAIMS A device for automatically adjusting an image condition comprising: a detector unit for detecting the brightness and ambient color temperature, and taking out the detected data; a video processor that receives and digitizes the output signals of the detector unit to obtain the brightness and ambient color temperature, and automatically adjust the brightness, contrast and color temperature of an image using the data obtained in consideration of a brightness, contrast and color temperature selected by a user; and an unfolding unit that presents the adjusted image on a screen.
2. A device of Claim 1, wherein the detecting unit is a sensor image that outputs the detected data by means of at least two electrical signals; and wherein the video processor digitizes at least two electrical signals to determine the environmental brightness and color temperature.
3. A device of Claim 2, wherein the sensor photo outputs electrical signals of cyan and yellow; and where the video processor determines the environmental brightness by adding the cyan and yellow outputs, and determines the environmental color temperature by taking the cyan output ratio and the yellow output.
4. 4. A device of Claim 2, wherein the video processor comprises: a storage unit that stores the brightness, contrast, and color temperature selected by the user; and a microprocessor that determines the environmental brightness and color temperature, and determines the relative variations of brightness, contrast and color temperature according to the determined environmental brightness and color temperature, said microprocessor outputs control signals to automatically adjust the brightness, the contrast and the color temperature of the image based on the relative variations and the stored brightness, contrast and color temperature.
5. 5. A device of Claim 4, wherein the screen displays the image on a color screen; and wherein the video processor further comprises: a preamplifier that amplifies a video signal according to the output of control signals of the microprocessor; and a video output unit that processes the amplified video signal and displays the processed video signal on the color screen.
6. A device of Claim 4, wherein the microprocessor comprises: a storage unit that stores the brightness, contrast and color temperature selected by the user, and stores reference environmental values of brightness and color temperature; a detection unit for determining environmental brightness and color temperature based on at least two electrical signals from the detector unit; a comparison unit for calculating the average environmental values of brightness and color temperature for a predetermined period of time, and for comparing the average environmental values with the environmental reference values stored in the storage unit to derive compared values; and a control unit for determining relative variations using the compared values, and outputting control signals to automatically adjust the image by a quantity based on the relative variations determined and the brightness, contrast and color temperature selected by the user.
7. 7. A device of Claim 6, wherein the detector unit outputs electrical signals of cyan and yellow; and the detection unit determines the environmental brightness and color temperature by summing the outputs of cyan and yellow, and determines the environmental color temperature by taking the ratio of the cyan output to the yellow output.
8. 8. A device of Claim 1, wherein the video processor automatically adjusts the brightness, contrast, and color temperature of an image if the user selects a self-regulating mode.
9. 9. A device of Claim 1, where the video processor automatically adjusts the brightness and contrast of an image if the user selects a self-adjusting mode for brightness and contrast, and automatically adjusts the color temperature of an image if the user selects a self-regulation mode for color temperature.
10. 10. A device of Claim 1, wherein the video processor automatically adjusts the brightness, contrast and color temperature of an image by gradually increasing or decreasing brightness, contrast and color temperature.
11. 11. A method for automatically adjusting an image condition comprising: (a) detecting an ambient brightness and color temperature, and taking out the detected data; (b) receiving and digitizing the detected data to obtain the brightness and ambient color temperature, and automatically adjusting the brightness, contrast and color temperature of an image using the data obtained in consideration of the selected brightness, contrast and color temperature by a user; and (c) display the adjusted image on a screen.
12. 12. A method of claim 11, wherein in step (a), extract the detected data by at least two electrical signals; and in step (b) digitize the at least two electrical signals to determine the environmental brightness and color temperature.
13. 13. A method of Claim 12, wherein in step (a), output the electrical signals of cyan and yellow; and in step (b), determine the environmental brightness by adding the outputs of cyan and yellow, and determine the environmental color temperature by taking the ratio of the cyan output to the yellow output.
14. A method of Claim 12, wherein step (b) comprises: (aa) storing the brightness, contrast, and color temperature selected by a user; (bb) determine the environmental brightness and color temperature, and determine the relative variations of brightness, contrast and color temperature according to the determined environmental brightness and color temperature; and (c) outputting control signals to automatically adjust the brightness, contrast and color temperature of the image based on relative variations and stored brightness, contrast and color temperature.
15. 15. A method of Claim 14, wherein step (b) further comprises: amplifying a video signal according to the output of the control signals.; and process the amplified video signal and present the processed video signal on the color screen.
16. 16. A method of Claim 14, wherein the step (bb) comprises: storing the brightness, contrast and color temperature selected by the user, and storing the reference values of environmental brightness and color temperature; determine environmental brightness and color temperature based on at least two electrical signals; calculating the average environmental brightness and color temperature values over a predetermined period of time, and comparing the average environmental values with the stored environmental reference values to obtain the compared values; and determining the relative variations using the compared values, and outputting control signals to automatically adjust the image by a quantity based on the relative variations and brightness, contrast and color temperature selected by the user. . A method of Claim 16, wherein the at least two electrical signals are cyan and yellow; and the environmental brightness is determined by adding the outputs of cyan and yellow, and the ambient color temperature is determined by taking the ratio of the cyan output to the yellow output. . A method of Claim 11, wherein the brightness, contrast and color temperature of an image is automatically adjusted if the user selects a self-regulating mode. . A method of Claim 11, wherein the brightness and contrast of an image are automatically adjusted if the user selects a self-adjusting mode for brightness and contrast, and the color temperature of an image is automatically adjusted if the user selects a auto regulation mode for color temperature. . A method of Claim 11, wherein the brightness, contrast and color temperature of an image is automatically adjusted by gradually increasing or decreasing brightness, contrast and color temperature.