Image sensor device comprising central locking

• US 7,038,183 B2
• Filed: 12/18/2001
• Issued: 05/02/2006
• Est. Priority Date: 12/21/2000
• Status: Expired due to Term

• Current Assignee: STMicroelectronics NV
• Original Assignee: STMicroelectronics NV
• Inventors: Benthien, Stephan
• Primary Examiner(s): PYO, KEVIN K
• Application Number:
  US10/451,461
• Publication Number:
  US 20040155247A1
• Time in Patent Office: 1,596 Days
• Field of Search: 250/208.1, 250/214.R, 250/214.1, 348/294, 348/296, 348/297, 348/301, 348/302, 348/304, 348/308, 348/299, 257290-292, 257/443, 257/445
• US Class Current: 250/208.1
• CPC Class Codes: H04N 25/53 Control of the integration time
• CPC Class Codes: H04N 25/76 Addressed sensors, e.g. MOS or CMOS sensors

Abstract

The invention relates to an image sensor device comprising a substrate, formed in CMOS technology, in particular, with an integrated semiconductor structure (ASIC) and, arranged above that, an optically active thin-film structure comprising in each case at least one layer made of doped and undoped amorphous silicon, spatially adjacent pixels in each case being formed in the horizontal plane, which pixels each have an optoelectronic transducer for converting incident light into an electric current proportional to the incident quantity of light, and also a charge store assigned to the optoelectronic transducer, the charge state of which charge store can be varied in a manner dependent on the light incident on the assigned optoelectronic transducer. Taking this as a departure point, the invention is based on the object of further developing an image sensor device of the stated type to the effect of avoiding image distortions in the case of moving objects, which is achieved according to the invention by virtue of the fact that the charge store is a capacitor (C_int), in which the photocurrent output by the optoelectronic transducer can be integrated during a predetermined measurement duration, and that a switching means (T_stop) that can be driven by a common control device is provided in each pixel, which switching means can be driven jointly for all the pixels of the image sensor device.

Claims

1. An image sensor device, comprising:

a substrate, formed in CMOS technology with an integrated semiconductor structure (ASIC) and spatially adjacent pixels in each case being formed in the horizontal plane of the image sensor device, which pixels each have an optoelectronic transducer for converting incident light into an electrical current proportional to the incident quantity of light and also a charge store assigned to the optoelectronic transducer, the charge state of which charge store can be varied in a manner dependent on the light incident on the assigned optoelectronic transducer, wherein the charge store is a capacitor in which photocurrent output by the optoelectronic transducer is integrated during a predetermined measurement duration, and in that a first switching means is provided in each pixel that can be driven by a common control device, which said first switching means is coupled to the transducer and can be driven jointly for a plurality of pixels of the image sensor device; and

a second switching means coupled to the transducer having a control input coupled to a bias voltage such that the second switching means switches from an off state to an on state in response to the first switching means switching from an on state to an off state, wherein the second switching means provides a current path through which photocurrent generated by the transducer is diverted while the first switching means is in the off state.

2. The image sensor device as claimed in claim 1, wherein the first switching means is a transistor.

3. The image sensor device as claimed in claim 1, wherein the image sensor device has a row of individual pixels.

4. The image sensor device as claimed in claim 1, wherein the image sensor device has an area arrangement of pixels.

5. An image sensor device having a plurality of pixels, comprising:

a transducer for converting light into an electrical current;

a capacitor;

a first switch coupled to the transducer; and

a second switch coupled to the transducer and the first switch, the second switch comprising a control terminal coupled to a bias voltage such that the second switch switches from an off state to an on state in response to the first switch switching from an on state to an off state, wherein the second switch provides a current path through which photocurrent generated by the transducer flows while the first switch is in the off state.

6. The image sensor of claim 5, wherein the first switch is coupled to the capacitor.

7. The image sensor of claim 5, wherein the transducer is provided with a supply voltage when the second switch is in an on state.

8. The image sensor of claim 5, wherein the bias voltage is at a voltage such that the second switch automatically switches to an on state when the first switch switches to an off state.

9. The image sensor of claim 5, wherein the capacitor is coupled to the transducer when the first switch is in the on state.

10. The image sensor of claim 5, wherein the first switch acts as a shutter for the image sensor.