Solid-state imaging device and electronic camera for monitoring quantity of incident light

• US 6,603,511 B1
• Filed: 03/19/1999
• Issued: 08/05/2003
• Est. Priority Date: 03/20/1998
• Status: Expired due to Term

• Current Assignee: Nikon Corporation
• Original Assignee: Nikon Corporation
• Inventors: Ishida, Tomohisa
• Primary Examiner(s): Garber, Wendy R.
• Assistant Examiner(s): Tillery, Rashawn N.
• Application Number:
  US09/273,307
• Time in Patent Office: 1,600 Days
• Field of Search: 348/294, 348/296, 348/297, 348/298, 348/299, 348/257, 257/222, 257/223, 257/230, 257/231
• US Class Current: 348/294
• CPC Class Codes: H01L 27/14818 Optical shielding
• CPC Class Codes: H01L 27/1485 Frame transfer
• CPC Class Codes: H01L 27/14887 Blooming suppression
• CPC Class Codes: H04N 23/71 Circuitry for evaluating the brightness variation
• CPC Class Codes: H04N 23/74 by influencing the scene brightness using illuminating means
• CPC Class Codes: H04N 25/53 Control of the integration time
• CPC Class Codes: H04N 25/702 SSIS architectures characterised by non-identical, non-equidistant or non-planar pixel layout
• CPC Class Codes: H04N 25/706 Pixels for exposure or ambient light measuring
• CPC Class Codes: H04N 25/72 using frame transfer [FT]

Abstract

Solid-state imaging devices and cameras using such devices are provided. The devices detect changes in light quantity, directly incident to a light-receiving portion, in real-time and then read light information at an optimum exposure level whenever estimates of the quantity of incident light are difficult to obtain and whenever the quantity of incident light suddenly changes from an estimated value. To such end, the devices include a charge-transfer portion that generates and stores signal charges in response to incident light and then transfers the signal charges, an output portion that outputs the signal charge as an electrical signal, a semiconductor region that generates an optical current in proportion to the quantity of incident light, a shading membrane having an aperture portion formed on the semiconductor region, and a read portion that reads out the optical current, generated by light incident to the semiconductor region through the aperture portion, to the exterior of the semiconductor region.

Claims

1. A solid-state imaging device, comprising:

a charge-transfer portion that generates and stores electrical signal charges in response to light incident on the charge-transfer portion, and transfers the signal charges;

an output portion that outputs the signal charges, received from the charge-transfer portion, as an electrical signal;

a semiconductor region that generates signal charges in proportion to the quantity of light incident on the semiconductor region; and

a shading membrane having an aperture portion formed on the semiconductor region.

3. The solid-state imaging device of either claim 1 or claim 2, further comprising a read portion that reads out signal charges, generated by light incident to the semiconductor region through the aperture portion, to the exterior of the semiconductor region.

2. A solid-state imaging device comprising:

a charge-transfer portion that generates and stores signal charges in response to light incident on the charge-transfer portion, and transfers the signal charges;

an output portion that outputs the signal charges, received from the charge-transfer portion, as an electrical signal;

a semiconductor region, formed adjacent the charge-transfer portion, through which a signal charge flows, the signal charge flowing through the semiconductor region being an excess charge generated by the charge-transfer portion, the semiconductor region also generating a signal charge in proportion to the quantity of light to the semiconductor region; and

a shading membrane having an aperture portion formed on the semiconductor region.

4. A solid-state imaging device, comprising:

a charge-transfer portion that generates and stores electrical signal charges in response to light incident on the charge-transfer portion and then transfers the signal charge;

an output portion that outputs the signal charges, received from the charge-transfer portion, as an electrical signal;

a plurality of semiconductor regions that generate signal charges in proportion to the quantity of light incident on the semiconductor regions;

a shading membrane having an aperture portion formed on the semiconductor region; and

a plurality of aperture areas formed from a plurality of apertures from among the aperture portions.

6. The solid-state imaging device of either claim 4 or claim 5, further comprising read portions, formed at each of the aperture areas, that read out signal charges, generated by light incident to the semiconductor regions through the aperture portions, to the exterior of the semiconductor regions.

5. A solid-state imaging device, comprising:

a plurality of charge-transfer portions that generate and store electrical signal charges in response to light incident on the charge-transfer portions, and that transfer the signal charges;

an output portion that outputs the signal charges, received from the charge-transfer portions, as an electrical signal;

a semiconductor region, formed adjacent to the charge-transfer portions, through which an electrical signal charge flows, the signal charge flowing through the semiconductor region being an excess charge generated by the charge-transfer portions, the semiconductor region also generating a signal charge in proportion to the quantity of light incident on the semiconductor region;

a shading membrane having an aperture portion formed on the semiconductor region; and

a plurality of aperture areas formed from a plurality of apertures from among the aperture portions.

7. A camera, comprising:

(a) a solid-state imaging device, comprising;

a charge-transfer portion that generates and stores electrical signal charges in response to light incident on the charge-transfer portion, and transfers the signal charges;

an output portion that outputs the signal charges, transferred from the charge-transfer portion, as an electrical signal;

a semiconductor region that generates an optical current in proportion to the quantity of light incident on the semiconductor region;

a shading membrane having an aperture portion formed on the semiconductor region; and

a read portion that reads out an optical current, generated by light incident on the semiconductor region through the aperture portion, to the exterior of the semiconductor region; and

(b) a shutter that blocks light incident to the solid-state imaging device;

(c) a current-integration circuit that converts the optical current read from the read portion into a corresponding voltage;

(d) a comparator that compares the voltage converted by the current-integration circuit to a reference voltage; and

(e) a controller that determines a timing to close the shutter responsively to the comparison result output by the comparator.

9. The camera of either claim 7 or claim 8, further comprising a strobe that illuminates light onto an object to be photographed, wherein the controller further determines a timing, in response to the comparison result produced by the comparator, to stop the strobe from generating light.

8. A camera, comprising:

(a) a solid-state imaging device, comprising;

a charge-transfer portion that generates and stores electrical signal charges in response to light incident on the charge-transfer portion and transfers the signal charges;

an output portion that outputs the signal charges, transferred from the charge-transfer portion, as an electrical signal;

a semiconductor region, formed adjacent the charge-transfer portion, through which a signal charge flows, the signal charge flowing through the semiconductor region being an excess charge generated by the charge-transfer portion, the semiconductor region also generating an optical current in proportion to the quantity of light incident on the semiconductor region;

a shading membrane having an aperture portion formed on the semiconductor region; and

a read portion that reads out the optical current, generated by light incident to the semiconductor region through the aperture portion, to the exterior of the semiconductor region;

(b) a shutter that blocks light incident to the solid-state imaging device;

(c) a current-integration circuit that converts the optical current read from the read portion into a corresponding voltage;

(d) a comparator that compares the voltage converted by the current-integration circuit to a reference voltage; and

(e) a controller that determines a timing in which to close the shutter in response to the comparison result produced by the comparator.