1. A high frequency filter comprising:
a signal input node;
a signal output node;
a plurality of thin film piezoelectric resonators being coupled with the signal input and the signal output nodes, and including at least one of a variable resonance thin film piezoelectric resonator which has a ferroelectric thin film polarized in its thickness direction, the ferroelectric thin film with an orientation full width at half maximum not smaller than 0.1\xb0 and not greater than 5\xb0, and a pair of electrodes formed on the opposite major surfaces of the thin film with variable resonance characteristics to be changed in response to an applied voltage between the pair of electrodes; and
a voltage source being connected to the variable resonance thin film piezoelectric resonator so that a filtering characteristic of the variable resonance thin film piezoelectric resonator is controlled by changing the voltage applied from the voltage source.
2. A high frequency filter comprising:
a signal input node;
a signal output node;
a first variable resonance thin film piezoelectric resonator being coupled in series with the signal input and the signal output nodes, which has a ferroelectric thin film polarized in the thickness direction and a pair of electrodes formed on the opposite major surfaces of the thin film with a variable resonance characteristic to be changed in response to an applied voltage between the pair of electrodes;
a second variable resonance thin film piezoelectric resonator being coupled in parallel with the signal input and the signal output nodes, which has a ferroelectric thin film polarized in the thickness direction and a pair of electrodes formed on the opposite major surfaces of the thin film with a variable resonance characteristic to be changed in response to an applied voltage between the pair of electrodes; and
a voltage source being connected to the first and second variable resonance thin film piezoelectric resonator to apply the voltage between the pair of electrodes so that a filtering characteristic of at least one of the variable resonance thin film piezoelectric resonators is controlled by changing the voltage applied from the voltage source, the voltage source being adapted to apply a variable voltage to one of the first variable resonance thin film piezoelectric resonators connected in series or the second variable resonance thin film piezoelectric resonator connected in parallel, and a constant voltage to the other thin film piezoelectric resonator.
3. A high frequency filter comprising:
a signal input node;
a signal output node;
a first variable resonance thin film piezoelectric resonator being coupled in series with the signal input and the signal output nodes, which has a ferroelectric thin film polarized in the thickness direction and a pair of electrodes formed on the opposite major surfaces of the thin film with a variable resonance characteristic to be changed in response to an applied voltage between the pair of electrodes;
a second variable resonance thin film piezoelectric resonator being coupled in parallel with the signal input and the signal output nodes, which has a ferroelectric thin film polarized in the thickness direction and a pair of electrodes formed on the opposite major surfaces of the thin film with a variable resonance characteristic to be changed in response to an applied voltage between the pair of electrodes; and
a voltage source being connected to the first and second variable resonance thin film piezoelectric resonator to apply the voltage between the pair of electrodes so that a filtering characteristic of at least one of the variable resonance thin film piezoelectric resonators is controlled by changing the voltage applied from the voltage source,
the filter comprising a variable voltage source changing the voltage applied to at least one of the thin film piezoelectric resonator connected in series and the thin film piezoelectric resonator connected in parallel to change at least one of a gap between the resonance frequency and the anti-resonance frequency of the thin film piezoelectric resonator connected in series and a gap between the resonance frequency and the anti-resonance frequency of the thin film piezoelectric resonator connected in parallel as the anti-resonance frequency of the thin film piezoelectric resonator connected in series and the resonance frequency of the thin film piezoelectric resonator connected in parallel are coincident with each other, whereby a rejection band of the filter is controlled.
4. A high frequency filter comprising:
a signal input node;
a signal output node;
a first variable resonance thin film piezoelectric resonator being coupled in series with the signal input and the signal output nodes, which has a ferroelectric thin film polarized in the thickness direction and a pair of electrodes formed on the opposite major surfaces of the thin film with a variable resonance characteristic to be changed in response to an applied voltage between the pair of electrodes;
a second variable resonance thin film piezoelectric resonator being coupled in parallel with the signal input and the signal output nodes, which has a ferroelectric thin film polarized in the thickness direction and a pair of electrodes formed on the opposite major surfaces of the thin film with a variable resonance characteristic to be changed in response to an applied voltage between the pair of electrodes; and
a voltage source being connected to the first and second variable resonance thin film piezoelectric resonator to apply the voltage between the pair of electrodes so that a filtering characteristic of at least one of the variable resonance thin film piezoelectric resonators is controlled by changing the voltage applied from the voltage source, the voltage source changing the voltage applied to the thin film piezoelectric resonator connected in series or the thin film piezoelectric resonator connected in parallel to select a pass band mode obtained when the resonance frequency of the thin film piezoelectric resonator connected in series and the anti-resonance frequency of the thin film piezoelectric resonator connected in parallel are substantially coincident with each other or all rejection band mode obtained when the resonance frequency of the thin film piezoelectric resonator connected in series and the resonance frequency of the thin film piezoelectric resonator connected in parallel are substantially coincident with each other.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A solid-state imaging device comprising:
a first substrate and a second substrate which have circuit elements constituting pixels disposed therein are electrically connected to each other, wherein
the pixels comprise:
a photoelectric conversion element disposed in the first substrate;
an amplifier circuit that amplifies a signal generated in the photoelectric conversion element to output the amplified signal;
a signal accumulation circuit which is disposed in the second substrate and accumulates the amplified signal which is output from the amplifier circuit without digitization thereof;
an output circuit that outputs the amplified signal accumulated in the signal accumulation circuit from the pixel;
a noise reduction circuit that reduces noise in the amplified signal which is output from the amplifier circuit;
a first reset circuit that resets the photoelectric conversion element;
a second reset circuit that resets an input section of the amplifier circuit;
a transfer circuit that transfers a signal generated in the photoelectric conversion element to the input section of the amplifier circuit;
a second amplifier circuit that amplifies the amplified signal accumulated in the signal accumulation circuit to output a second amplified signal; and
a third reset circuit that resets an input section of the second amplifier circuit,
wherein the noise reduction circuit removes noise generated in an input section of the amplifier circuit resulting from an operation of a circuit connected to the amplifier circuit or noise resulting from the operating characteristics of the amplifier circuit
the noise reduction circuit includes:
a clamp section that clamps the amplified signal which is output from the amplifier circuit; and
a sample-and-hold section that samples and holds a signal corresponding to the amplified signal clamped in the clamp section and accumulates the amplified signal in the signal accumulation circuit.
2. The solid-state imaging device according to claim 1, wherein
the second reset circuit resets the input sections of the amplifier circuits of all the pixels collectively after the first reset circuits reset the photoelectric conversion elements of all the pixels collectively,
the clamp section clamps the amplified signal which is output from the amplifier circuit after the input section of the amplifier circuit is reset,
the transfer circuit transfers signals generated in the photoelectric conversion elements of all the pixels collectively to the input section of the amplifier circuit after elapsing a predetermined period until the first reset circuits reset the photoelectric conversion element of all the pixels collectively, and
the sample-and-hold section samples and holds a signal corresponding to a fluctuation in the amplified signal generated by transferring the signal by the transfer circuit and accumulates the sampled and held signal in the signal accumulation circuit, and then, the output circuit outputs the second amplified signal after the sample-and-hold section samples and holds the signal corresponding to the fluctuation in the amplified signal generated by transferring the signal by the transfer circuit and accumulates the sampled and held signal in the signal accumulation circuit and the second amplified signal after the third reset circuit resets the input section of the second amplifier circuit are output from the pixel in a time-division manner.
3. The solid-state imaging device according to claim 1, further comprising
a differential processing circuit that performs differential processing on two kinds of signals which are output by the output circuit.
4. The solid-state imaging device according to claim 1, wherein
the second reset circuit resets the input sections of the amplifier circuits of all the pixels collectively after the first reset circuits reset the photoelectric conversion elements of all the pixels collectively,
the clamp section clamps the amplified signal which is output from the amplifier circuit after the input section of the amplifier circuit is reset,
the transfer circuit transfers signals generated in the photoelectric conversion elements of all the pixels collectively to the input section of the amplifier circuit after elapsing a predetermined period until the first reset circuits reset the photoelectric conversion element of all the pixels collectively,
the sample-and-hold section samples and holds a signal corresponding to a fluctuation in the amplified signal generated by transferring the signal by the transfer circuit and accumulates the sampled and held signal in the signal accumulation circuit, and
the output circuit outputs the second amplified signal after the sample-and-hold section samples and holds the signal corresponding to the fluctuation in the amplified signal generated by transferring the signal by the transfer circuit and accumulates the sampled and held signal in the signal accumulation circuit and the second amplified signal when the third reset circuit resets the input section of the second amplifier circuit are output from the pixel in a time-division manner.