US 2001/0055068 A1 · Solid state imaging device

Abstract

An imaging device uses a solid state imaging element, during multi-field accumulation to prevent shading and oscillatory phenomena such as repeated black and white patterns. A signal is supplied from a timing signal generation circuit to switches, and controls the ON/OFF operation. During the H period of the signal, the switch is closed, and the output value of an amplifier is input to a capacitor. During the L period of the signal, the switch is opened, and the average value of the output of the amplifier is maintained in the capacitor. During the H period, the switch is open, while during the L period, the switch is in the ON state. At this time, the level of the capacitor C2 and the output of the amplifier are input to an amplifier, and their difference is amplified and supplied to a capacitor C3 via the switch.

Claims15

Dependent claims

A solid state imaging device, comprising:

a solid state imaging element;
a timing signal generation circuit which generates an optical black clock pulse indicating an optical black section and an enable signal indicating timing at which an output from said solid state imaging elements stops;
and
a clamping means, comprising a target value setting means which sets a target value for output and an amplifier means which amplifies the difference between said target value and an optical black signal obtained at a timing of said optical black clock;
and which, along with feeding back said difference value, matches a signal level of said optical black section outputted from said solid state imaging element to a constant value by maintaining said target value of said optical black section while said enable signal outputted from said timing signal generation circuit is being obtained.

2 more elements

A solid state imaging device which comprises a solid state imaging element, and a clamping means which matches the signal level of an optical black section outputted from said solid state imaging element to a constant value, in which said clamping means comprises:

a first amplifier means which inputs the output of said solid state imaging element at one of its input terminals;
a first sampling means, which includes a retention section, and a switch which operates including said optical black section outside a vertical blanking period, and which samples the output of said first amplifier means;
a target value setting means which sets a target value for output;
a second amplifier means which receives an output from said first sampling means and an target value level from said target value setting means via a low pass filter means, amplifies the difference between them, and inputs it to said first amplifier means;
a second sampling means which samples the output of said second amplifier means during a period in which an output signal is obtained from said solid state imaging element;
a third amplifier means which amplifies the difference between the output of said second amplifier means and the output of said second sampling means;
and
a switching means which inputs the output of said third amplifier means to said first sampling means during a period in which no signal is being outputted from said solid state imaging element, and inputs the output of said first amplifier means to said first sampling means during a period in which a signal is being outputted from said solid state imaging element.

5 more elements

Dependencies are inferred from the claim text.

Solid state imaging device

Life of this patent

Solid state imaging device

Life of this patent

Abstract

Claims15