Abstract: A bipolar junction transistor includes a semiconductor island on an insulating substrate; an emitter and at least one of a collector and sub collector within the semiconductor island, the emitter and the at least one of the collector and the sub collector being of a first conductivity type; a base within the semiconductor island separating the emitter and the at least one of the collector and the sub collector, the base being of a second conductivity type; a base contact region within the semiconductor island, the base contact region being of the second conductivity type; and a connecting base region adjacent the base within the semiconductor island and connecting the base to the base contact region while not directly contacting the emitter, the connecting base region being of the second conductivity type with a doping concentration less than a doping concentration of the base contact region.

Abstract: A charge storage circuit for a pixel comprises a charge storage node. First and second series-connected transistors (8,10) are provided for selectively isolating the charge storage node from a first voltage input (9,SL) for supplying a data voltage. The circuit is provided with a voltage follower circuit for replicating a voltage at the charge storage node (12) at another node in the circuit thereby to reduce the drain-source voltage across the second transistor (10). The first transistor forms part of the voltage follower circuit.

Abstract: An active matrix substrate in which variations in output characteristics of photodiodes are reduced, and a display device using this active matrix substrate, are provided. An active matrix substrate (1) having an n-TFT (20), a p-TFT (30), and a photodiode (10) is used. The photodiode (10) includes a p-layer (7), an i-layer (8), and an n-layer (9). The i-layer (8) includes a p-type semiconductor region (8a) at a position adjacent to the player (7), said p-type semiconductor region (8a) having a diffusion concentration of p-type impurities that is set at the same level as that of a diffusion concentration of p-type impurities in the channel region (23) of the n-TFT (20); and an n-type semiconductor region (8b) at a position adjacent to the n-layer (9), said n-type semiconductor region (8b) having a diffusion concentration of n-type impurities that is set at the same level as that of a diffusion concentration of n-type impurities in the channel region (33) of the p-TFT (30).

Abstract: An array element for a temperature sensor array circuit.

Abstract: An apparatus for acquiring an image comprises a display (60), such as an LCD and backlight, for illuminating the object. A photosensor array (61) detects light reflected from the object. A controller (62) causes the display (60) and the photosensor array (61) to: illuminate the object (100); acquire (102) a first image (104) of the object; display a first illuminating pattern (106) for illuminating the object, which first illuminating pattern is derived (108) from the first image; and acquire (102) a second image (110) of the object illuminated by the first illuminating pattern (106). The controller (62) preferably causes the display (60) and the photosensor array (61) to: display a second illuminating pattern (112) for illuminating the object, which second illuminating pattern is derived (108) from at least the second image; and acquire a third image (114) of the object illuminated by the second illuminating pattern (112).

Abstract: A light sensor comprises a first photodetector (52) sensitive in a first wavelength range; a second photodetector (60) sensitive in a second wavelength range different from the first wavelength range; and a processor for determining, using the output of the second photodetector, a correction to the output of the first photodetector for compensating the output of the first photodetector for a difference between the spectral response characteristic of the first photodetector and a reference spectral response characteristic. The processor is adapted to apply the correction to the output of the first photodetector. For example, the first photodetector (52) may be sensitive over the entire visible wavelength range and the second photodetector (60) may be sensitive in a blue wavelength range—this allows the output of the first photodetector to be corrected for an increased sensitivity in the blue wavelength range compared to the reference spectral response characteristic.

Abstract: A thin film transistor is formed in a semiconductor island on an insulating substrate. The transistor comprises a source (1502) and a drain (1504) of first conductivity type and a channel (1508) of a second opposite conductivity type. The channel is overlapped by one or more insulated gates (1510) and is provided with isolation diodes. Each isolation diode comprises a first region (1506) which is lightly doped and a second region (1512) which is heavily doped and of the second conductivity type. The diodes are not overlapped by the gate (1510). The first and second regions (1506, 1512) extend away from the channel (1508) by less than the length of the adjacent source or drain.

Abstract: A photosensitive structure comprises a plurality of photosenstivie regions (124) which are electrically in series. A light shading layer comprises a plurality of electrically conductive regions (501) disposed so as to shade the photosensitive regions (124) from light incident on a major surface of the structure. The conductive regions (501) are electrically isolated from each other.

Abstract: A light sensing system comprises a first light sensor (21?), a second light sensor (21) and a first light shielding material (24) disposed over the first light sensor (21?) but not over the second light sensor (21) so as to block ambient light from being incident on the first light sensor (21). A first electrically conductive material (23a) is disposed between the first light shielding layer (24) and the first light sensor and a second electrically conductive material (23b) is disposed over the second light sensor. The second electrically conductive material (23b) is at least partially light-transmissive. Providing the first electrically conductive material (23a) between the first light shielding layer (24) and the first light sensor eliminates any parasitic capacitance that would otherwise be set up by the light shielding layer (24) (which is typically a metallic layer).

Abstract: An illumination system comprises at least two light sources (101,102,103) having different emission spectra to one another; a detection circuit (131,132,133) for sensing a light intensity using at least one of the light sources as a photosensor; and driving means (161,162,163) for driving the light source in dependence on the sensed spectral distribution of light. The emission spectrum of a light source with the smallest bandgap overlaps the emission spectrum of a light source with the second-smallest bandgap. The illumination system is possible to measure the intensity of light emitted by the light source with the smallest bandgap by putting the light source with the second-smallest bandgap in detection mode. The illumination system may also sense the spectral distribution of ambient light, to allow the output from the illumination system to be adjusted in dependence on the ambient light.

Abstract: An active matrix substrate in which variations in output characteristics of photodiodes are reduced, and a display device using this active matrix substrate, are provided. An active matrix substrate (1) having an n-TFT (20), a p-TFT (30), and a photodiode (10) is used. The photodiode (10) includes a p-layer (7), an i-layer (8), and an n-layer (9). The i-layer (8) includes a p-type semiconductor region (8a) at a position adjacent to the player (7), said p-type semiconductor region (8a) having a diffusion concentration of p-type impurities that is set at the same level as that of a diffusion concentration of p-type impurities in the channel region (23) of the n-TFT (20); and an n-type semiconductor region (8b) at a position adjacent to the n-layer (9), said n-type semiconductor region (8b) having a diffusion concentration of n-type impurities that is set at the same level as that of a diffusion concentration of n-type impurities in the channel region (33) of the p-TFT (30).

Abstract: The present invention provides a liquid crystal display device capable of preventing the occurrence of dark currents in photodiodes. Thus, the liquid crystal display device includes a liquid crystal display panel 1 including an active matrix substrate and a backlight 13 for illuminating the liquid crystal display panel. The active matrix substrate 1 includes a photodiode 7 formed by a silicon film and a light shielding film 8 for shielding the photodiode 7 against illumination light from the backlight 13. The photodiode 7 and the light shielding film 8 are provided on a base substrate 5. The light shielding film 8 is formed by a semiconductor or an insulator. Preferably, the photodiode 7 is made of, for example, polycrystalline silicon or continuous grain silicon so as to have a characteristic that its sensitivity increases as the wavelength of light entering the photodiode becomes shorter.

Abstract: A light shield (204) for blocking light traveling toward a PIN photodiode (413) from a glass substrate (314) side is formed of a conductive material, and a reference electric potential (Vr?nVoc) equal to that of a cathode of the PIN photodiode (413) is applied to the light shield (204) from a power supply circuit (266). Thus, inductive noise for a photoelectric conversion device used for an ambient light sensor is further reduced in a display device.

Abstract: A method is provided of compensating for stray light in a light sensor having a detection photosensor (7) and a reference photosensor (20), the reference photosensor (7) being for use in compensating for stray light falling on the detection photosensor (20). The method comprises using the reference photosensor (20) at least in part to determine a bias voltage applied to the detection photosensor (7). Based on this method, a display device is provided comprising a backlight and a light sensor for determining an ambient light level with the effects of stray light from the backlight substantially removed, with means provided for controlling the intensity of the backlight in dependence upon the determined ambient light level.

Abstract: In a liquid crystal display device (1), (i) regions where respective detecting devices (201) are provided and (ii) regions where respective reference devices (202) are provided are separately arranged so as to be alternated along a frame. In each region, a predetermined number of PIN photodiodes (413) are connected in series and in parallel. In the whole of the first regions, (i) a series connection of n PIN photodiode(s) and (ii) a predetermined number of parallel connections are provided; in the whole of the second regions, (i) a series connection of n PIN photodiode(s) and (ii) a predetermined number of parallel connections are provided. Thus, even in a case where there is a great variation in the characteristics of photoelectric conversion device elements in a display panel which photoelectric conversion device elements configure a photoelectric conversion device, an intensity of ambient light can be detected accurately in the display device.

Abstract: A method of operating a photosensor comprising: applying a bias voltage to a photosensor (12) comprising n (n>1) photo-sensitive elements (8) connected in series, and determining the photocurrent in the photosensor (12) at a time when the applied bias voltage across the photosensor maintains the photosensor at or close to the point at which it has the greatest signal-to-noise ratio. This may conveniently be done by determining the current in the photosensor at a time when the applied bias voltage across the photosensor is equal or approximately equal to n×Vbi, where Vbi is the bias voltage about which the current in a single one of the photo-sensitive elements (8), in the dark, changes sign. In an embodiment in which the photo-sensitive elements (8) are photodiodes, the bias voltage Vbi is the “built-in” voltage of the photodiodes. The photocurrent generated when n series-connected photodiodes are illuminated is approximately equal to the photocurrent generated when one photodiode is illuminated.