Abstract:
A display includes a housing including a frame, a panel fixedly arranged inside the frame and including a front pane which presents a picture visible in a viewing area substantially in front of the front pane, a sensor fixedly coupled to the housing and arranged in the viewing area in front of the front pane which receives at least one spectral radiation component of the picture emitted by the panel, and wherein the sensor is fixed on the frame such that it receives visible radiation of a surrounding area of the display.

Description:
RELATED APPLICATION 
       [0001]    This application claims priority of European Patent Application No. 09168851.5, filed Aug. 27, 2009, herein incorporated by reference. 
       TECHNICAL FIELD 
       [0002]    This disclosure relates to a display which is, for example, used for televisions or personal computers. Such displays may loose luminosity during their lifetime. 
       BACKGROUND 
       [0003]    US 2009/0160834 A1 discloses a display screen with a display area which includes a frame and a sensor module. The frame surrounds the display area. The sensor module is mounted on the frame and includes a mount disposed on the frame and a slidable assembly slidably disposed on the mount and including an ambient light sensor and a screen light sensor, wherein the ambient light sensor and the screen light sensor are disposed on two opposite sides of the slidable assembly respectively. 
         [0004]    US 2001/0008395 A1 discloses an image display device. The image display device has a sensor which measures how R, G, and B light is emitted to display an image on a display panel. According to the measurement value obtained from the sensor, the power with which to drive a light source that supplies light needed for the display operation of the display panel is varied so that the brightness or chromaticity of the display panel is corrected. 
         [0005]    EP 1 274 066 A1 discloses a system and method for real time correction of light output and/or color of an image displayed on a display device. The system comprises: a display device comprising an active display area for displaying the image, an image forming device and an electronic driving system for driving the image forming device, an optical sensor unit comprising an optical aperture and a light sensor having an optical axis, to make optical measurements on a light output from a representative part of the active display area of the image forming device and generating optical measurement signals therefrom, a feedback system receiving the optical measurement signals and on the basis thereof controlling the electronic driving system. 
         [0006]    It could be helpful to provide a display with a constant luminosity during the whole lifetime of the display. 
       SUMMARY 
       [0007]    I provide a display including a housing including a frame, a panel fixedly arranged inside the frame and including a front pane which presents a picture visible in a viewing area substantially in front of the front pane, a sensor fixedly coupled to the housing and arranged in the viewing area in front of the front pane which receives at least one spectral radiation component of the picture emitted by the panel, and wherein the sensor is fixed on the frame such that it receives visible radiation of a surrounding area of the display. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]      FIG. 1  shows a display in a perspective view; 
           [0009]      FIG. 2  shows an enlarged representation of a panel of the display in a schematic view; 
           [0010]      FIG. 3  shows a further enlarged representation of the panel in a sectional view; and 
           [0011]      FIG. 4  shows a control unit and the panel of the display in a schematic view. 
       
    
    
     DETAILED DESCRIPTION 
       [0012]    It will be appreciated that the following description is intended to refer to specific examples of structure selected for illustration in the drawings and is not intended to define or limit the disclosure, other than in the appended claims. 
         [0013]    My display comprises a housing and a panel. The panel is fixedly arranged inside the housing and comprises a front pane. The front pane is designed for presentation of a picture visible in a room area in front of the front pane. A sensor is fixedly coupled to the housing or to the panel. The sensor is arranged in the room area in front of the front pane and is designed to receive the intensity of at least one spectral radiation component of the picture emitted by the panel. The housing comprises a frame. The panel is arranged inside the frame and the sensor is fixedly arranged on the frame. The sensor is arranged and designed to receive the intensity of the visible radiation of a surrounding area of the display. 
         [0014]    In particular, the sensor is positioned in an area in which the picture emitted by the display may be seen totally or at least partially. 
         [0015]    This has the advantage that the luminosity of the at least one spectral radiation component may be kept constant during the whole life-time of the display by directly controlling the luminosity of the picture as it can be seen by the viewer. A further advantage is that the whole front surface of the panel may be used by the viewer in an undisturbed manner and without obstacles. A further advantage is that the luminosity of the panel may be adapted to the luminosity of the surrounding area of the display. 
         [0016]    The panel may comprise a plurality of pixels. Each of the pixels comprises base color pixels for the emission of three base colors. The sensor is designed to receive the intensity of the spectral radiation component of at least one of the three base colors of the picture. The luminosity of one or more of the three base colors may be kept constant during the whole life-time of the display. 
         [0017]    The panel may also comprise a plurality of pixels. Each of the pixels comprises base color pixels for the emission of three base colors. The sensor is designed to receive the intensity of the sum of the spectral radiation components of the three base colors of the picture. The luminosity of the sum of the spectral radiation components of the three base colors may be kept constant during the whole life-time of the display. 
         [0018]    The panel may further comprise a plurality of pixels. The pixels are designed for the emission of a mixing color. The sensor is designed to receive the intensity of the radiation component of the mixing color of the picture. In particular, the mixing color may be the color “white” which may be preferably used in black-white displays. This has the advantage that the luminosity of the mixing color may be kept constant during the whole life-time of the display. 
         [0019]    The display may have a signal input which is designed for the input of a video signal, and a control unit. The control unit is electrically coupled with the signal input and is designed to control the luminosity of the panel depending on the video signal. The sensor is designed for the output of at least one output signal representative for the intensity of the at least one spectral radiation component of the picture and/or for the intensity of the visible radiation of the surrounding area of the display. The sensor is electrically coupled to the control unit. The control unit is designed to control the panel depending on the at least one output signal of the sensor. 
         [0020]    The luminosity of the panel may thus be kept constant after the start or an operation break of the display. 
         [0021]    The panel may be a liquid crystal panel. 
         [0022]    Turning now to the drawings, elements of the same design and function that occur in different illustrations are identified by the same reference character. 
         [0023]      FIG. 1  shows a display  10 . The display  10  is designed as a flat screen display. However, the display  10  may be in other forms known in the art. 
         [0024]    The display  10  has a housing  12  which is mechanically coupled to a base  14 . The base  14  carries the display  10 . The housing  12  has a frame  16 . A panel  18  is fixedly arranged inside the frame  16 . In  FIG. 1 , the panel  18  is a liquid crystal panel. 
         [0025]    The display  10  is arranged, located or positioned in a surrounding or viewing area  20 . 
         [0026]      FIG. 2  shows the panel  18  which is designed as a liquid crystal panel in an enlarged representation. The panel  18  designed as a liquid crystal panel has a background lighting  22 . Radiation emitted by the background lighting  22  is received by a liquid crystal cell  24 . The liquid crystal cell  24  comprises a plurality of pixels  25 . In  FIG. 2 , the pixels  25  comprise basic color pixels R, G, B, which are in particular designed to emit three basic colors red, green and blue. By applying a voltage to the pixels  25  of the crystal liquid cell  24  the direction of polarization of the pixels  25  may be changed individually. By this a transmission of the radiation of the background lighting  22  or a shading of the radiation of the background lighting  22  can be obtained for the basic color pixels R, G, B. 
         [0027]    The panel  18  furthermore has a front pane  26  with a front surface  28 . The front pane  26  may present a picture. The front pane  26  is designed for the transmission of at least one spectral radiation component  30 . The spectral radiation component  30  is a portion of the visible spectrum of the light. 
         [0028]    In  FIG. 2 , the front pane  26  comprises a sensor  32  which is arranged on the front surface  28 . By this, the sensor  32  is fixedly coupled to the panel  18 . The functions of the sensor  32  will be described in the following in detail. 
         [0029]    In the display  10  shown in  FIG. 1 , the sensor  32  is fixedly arranged on the frame  16 . By this, the sensor  32  is fixedly coupled to the housing  12 . 
         [0030]      FIG. 3  shows a schematic view of a part of the display  10 . The panel  18  is emitting visible spectral radiation components  30  of the picture through the front surface  28  of the front pane  26  into a room area  34  in front of the front pane  26 . The room area  34  in front of the front pane  26  is the area in which a viewer may watch the picture on the panel  18 . This means that the picture presented by the panel  18  may be visible in the whole room area  34  in front of the front pane  26 . 
         [0031]    In the display  10  shown in  FIG. 1 , the sensor  32  is fixedly arranged on the frame  16 . 
         [0032]    The sensor  32  may receive the intensity of at least one component  30  of the visible radiation of the picture emitted by the panel  18 . Furthermore, the sensor  32  may preferably receive the intensity of the visible radiation of a surrounding area  20  of the display  10 . 
         [0033]    Preferably, the sensor  32  can receive the intensity of one of the three basic colors of the radiation components  30  of the picture emitted by the panel  18 . 
         [0034]    Further preferably, the sensor  32  may receive the intensity of the sum of the emitted spectral radiation components  30  of the picture emitted by the panel  18 . In particular, the sensor  32  may receive the intensity of the sum of the emitted spectral radiation components  30  of the basic color pixels R, G, B. 
         [0035]    Further preferably, the pixels  25  are designed to emit a mixing color. In this case, it is advantageous if the sensor  32  may receive the emitted spectral radiation components  30  of the picture emitted by the panel  18 . In particular, the mixing color may be the color “white.” This color is preferably used with black-white panels. 
         [0036]      FIG. 4  shows the panel  18  and a control unit  36 . The panel  18  is electrically coupled to the control unit  36  by control lines and a signal input  38 . A video signal  40  from the control unit  36  can reach the panel  18  via the signal input  38 . The control unit  36  may control the luminosity of the panel  18  depending on the properties of the video signal  40 . 
         [0037]    The control unit further comprises a PC input  42 . A PC signal  44  can reach the control unit  36  for the controlling of the panel  18  via the PC input  42 . 
         [0038]    The control unit  36  comprises a further signal input  46 . An output signal  48  of the sensor  32  can reach the control unit  36  by the further signal input  46 . The output signal  48  of the sensor  32  or the output signals  48  of the sensor  32  respectively are representative for the intensity of the spectral radiation components  30  of the picture emitted by the panel  18  and/or for the intensity of the visible radiation of the surrounding area  20  of the display  10 . The control unit  36  may control the luminosity of the panel  18  depending on the at least one output signal  48  of the sensor  32 . 
         [0039]    The panel  10  has the advantage that the total luminosity of the radiation components  30  or the luminosity of one or more of the basic colors red, green or blue emitted by the display  10  may have a high stability over the lifetime of the display  10 . Depending from the output signal  48  of the sensor  32  with a value which is a measure for the intensity of the radiation components  30  emitted by the panel  18  via the front surface  28  of the front panel  26  the pixels  25  and/or the basic color pixels R, G, B may be controlled by the control unit  36 . Thus, a high stability of the total luminosity or a high stability of the luminosity of one or more of the basic colors red, green or blue may be obtained over the lifetime of the display  10 . 
         [0040]    By receiving the intensity of the visible radiation of the surrounding area  20  of the display  10  it is possible to control the pixels  25  and/or the basic color pixels R, G, B. Therefore, the intensity of the radiation components  30  of the picture may be adapted depending on the intensity of the lightning of the surrounding area  20  of the display  10 . 
         [0041]    A further advantage of the display  10  is that in view of professional applications such as medical, CAD/CAM and/or graphic applications, there is a high capability to maintain a very good image performance consistently over the lifetime of the display  10 . In particular, a stabilization of the real time brightness over the lifetime of the display  10  is possible. Furthermore, control of the color chromaticity in a very narrow tolerance band is possible. Furthermore, an adjustment of the display  10  as a function of the illumination in the surrounding area  20  is possible. Finally, it is possible to verify and recalibrate the gamma curve and obtain the standards of digital imaging and communications in medicine (DICOM). DICOM is a standard to adjust the Gray scale tone characteristics of displays used in the medical field. An image performance track in the calibration may be carried out without additional hardware or further tools. An incorporated luminance and color engine may automatically adjust related parameters. Stabilization of luminance may be possible within a very short time period of, for example, a few seconds after the start-up of the display  10 . Image luminance drift problems during a warm-up period of the panel  18  may be avoided. The luminance output value may be set according to the preference of the end user if the preset luminance is not satisfactory for the application. 
         [0042]    Although the apparatus and has been described in connection with specific forms thereof, it will be appreciated that a wide variety of equivalents may be substituted for the specified elements described herein without departing from the spirit and scope of this disclosure as described in the appended claims. 
       REFERENCES 
       [0000]    
       
           10  display 
           12  housing 
           14  base 
           16  frame 
           18  panel 
           20  surrounding area 
           22  back ground lightning 
           24  liquid crystal cell 
           25  pixels 
           26  front pane 
           28  front surface 
           30  radiation component 
           32  sensor 
           34  room area 
           36  control unit 
           38  signal input 
           40  video signal 
           42  PC input 
           44  PC signal 
           46  further signal input 
           48  output signal of  32   
         R,G,B basic colour pixel