Photoconductor readout device and method of using same for determining responsivity and detectivity

Patent metadata

Field	Value
Publication number	US-11988552-B2
Application number	US-202017765949-A
Country	US
Kind code	B2
Filing date	Oct 8, 2020
Priority date	Oct 9, 2019
Publication date	May 21, 2024
Grant date	May 21, 2024

Abstract

A device includes at least one array of photoconductors, at least one bias voltage source, and at least one photoconductor readout circuit. Each photoconductor is configured for exhibiting an electrical resistance dependent on an illumination of its light-sensitive region, and at least one photoconductor of the array is designed as characterizing photoconductor. The bias voltage source is configured for applying at least one alternating bias voltage to the characterizing photoconductor or at least one direct current (DC) bias voltage to the characterizing photoconductor. The photoconductor readout circuit is configured for determining of a response voltage of the characterizing photoconductor generated in response to the bias voltage. The response voltage is proportional to a variable characterizing the array of photoconductors. The photoconductor readout circuit configured for determining of the response voltage of the characterizing photoconductor during operation of the array of photoconductors.

First claim

The invention claimed is:

1. A device comprising:
at least one array of photoconductors, wherein each photoconductor is configured for exhibiting an electrical resistance dependent on an illumination of a light-sensitive region of each photoconductor, wherein at least one photoconductor of the at least one array of photoconductors is designed as a characterizing photoconductor;
at least one bias voltage source, wherein the bias voltage source is configured for applying at least one alternating bias voltage to the characterizing photoconductor or at least one direct current (DC) bias voltage to the characterizing photoconductor;
at least one photoconductor readout circuit, wherein the photoconductor readout circuit is configured for determining of a response voltage of the characterizing photoconductor generated in response to the bias voltage, wherein the response voltage is proportional to a variable characterizing the at least one array of photoconductors, wherein the variable characterizing the at least one array of photoconductors is at least one variable selected from a group consisting of dark resistance R dark , signal noise, and signal response to a known intensity, wherein the photoconductor readout circuit is configured for determining of the response voltage of the characterizing photoconductor during operation of the at least one array of photoconductors; and
at least one evaluation device, wherein the evaluation device is configured for determining responsivity R from the signal response to the known intensity and detectivity D* from the signal response to the known intensity and from signal noise.

2. The device according to claim 1 , wherein the evaluation device is configured for estimating responsivity of each photoconductor of the at least one array of photoconductors considering the measured responsivity R of the characterizing photoconductor and/or wherein the evaluation device is configured for estimating detectivity of each photoconductor of the at least one array of photoconductors considering the measured detectivity D* of the characterizing photoconductor.

3. The device according to claim 1 , wherein the characterizing photoconductor is covered with at least one opaque mask, wherein the photoconductor readout circuit is configured for determining the response voltage of the characterizing photoconductor generated in response to the alternating bias voltage, wherein the response voltage is proportional to the dark resistance R dark of the characterizing photoconductor.

4. The device according to claim 1 , wherein the characterizing photoconductor is covered with at least one opaque mask, wherein the photoconductor readout circuit is configured for determining the response voltage of the characterizing photoconductor generated in response to the DC bias voltage, wherein the response voltage is proportional to the signal noise.

5. The device according to claim 1 , wherein the characterizing photoconductor is covered with at least one wavelength dependent filter, wherein the photoconductor readout circuit is configured for determining the response voltage of the characterizing photoconductor generated in response to the DC bias voltage, wherein the response voltage is proportional to the signal response to the known intensity.

6. The device according to claim 5 , wherein the device comprises at least one narrow band illumination source configured for generating light having a pre-defined and/or pre-determined intensity P, wherein a source wavelength of the narrow band illumination source is detectable by the characterizing photoconductor being covered with the wavelength dependent filter and is outside the wavelengths used by the other photoconductors of the array, wherein the photoconductor readout circuit is configured for determining the response voltage S of the characterizing photoconductor being covered with the wavelength dependent filter generated in response to illumination of its light-sensitive region by the narrow band illumination source.

7. The device according to claim 1 , wherein each photoconductor responds to electromagnetic energy of a different wavelength.

8. The device according to claim 1 , wherein the device is a spectrometer device; an agrochemical quality control device; a pharmaceutical quality control device; a food quality control device; or an atmospheric science device.

9. A method for determining at least one variable characterizing at least one array of photoconductors, the method comprising:
i) providing at least one array of photoconductors, wherein each photoconductor is configured for exhibiting an electrical resistance dependent on an illumination of a light-sensitive region of each photoconductor, wherein at least one photoconductor of the at least one array of photoconductors is designed as a characterizing photoconductor;
ii) applying at least one alternating bias voltage to the characterizing photoconductor or at least one direct current (DC) bias voltage to the characterizing photoconductor by using at least one bias voltage source;
iii) determining a response voltage of the characterizing photoconductor generated in response to the bias voltage, wherein the response voltage is proportional to the variable characterizing the at least one array of photoconductors, wherein the variable characterizing the at least one array of photoconductors is at least one variable selected from a group consisting of dark resistance R dark , signal noise, and signal response to a known intensity, wherein determining the response voltage of the characterizing photoconductor is performed during operation of the at least one array of photoconductors; and
iv determining responsivity R from the signal response to the known intensity and detectivity D* from the signal response to the known intensity and from signal noise with at least one evaluation device.

10. The method according to claim 9 , wherein the variable characterizing the at least one array of photoconductors is a signal response to a known intensity, wherein the characterizing photoconductor of the at least one array of photoconductors is covered with at least one wavelength dependent filter, wherein in step ii) the direct current (DC) bias voltage is applied to the characterizing photoconductor, wherein the method further comprises illuminating the characterizing photoconductor by using at least one narrow band illumination source, wherein the narrow band illumination source is configured for generating light having a pre-defined and/or pre-determined intensity P, wherein a source wavelength of the narrow band illumination source is detectable by the characterizing photoconductor and is outside the wavelengths used by the other photoconductors of the array, wherein in step iii) the response voltage of the characterizing photoconductor generated in response to illumination of the light-sensitive region of the characterizing photoconductors by the narrow band illumination source is determined, wherein the response voltage is proportional to the signal response to the known intensity.

11. The method according to claim 9 , wherein the variable characterizing the array of photoconductors is signal noise N, wherein the characterizing photoconductor is covered with at least one opaque mask, wherein in step ii) the direct current (DC) bias voltage is applied to the characterizing photoconductor, wherein in step iii) the signal noise N is determined by determining the response voltage of the characterizing photoconductor generated in response to the DC bias voltage.

12. The method according to claim 9 , wherein the variable characterizing the array of photoconductors is dark resistance R dark , whe

Assignees

• Trinamix Gmbh

Inventors

• Feuerstein Bertram
• Valouch Sebastian
• Gust Robert
• Klueh Stefan
• Send Robert
• Gould Darren Richard

Classifications

• G01J1/4228 Primary

  arrangements with two or more detectors, e.g. for sensitivity compensation · CPC title

• G01J1/46 Primary

  using a capacitor · CPC title

• G01J3/2803

  using photoelectric array detector · CPC title

• G01J5/22

  Electrical features thereof · CPC title

• G01J2001/4446

  Type of detector · CPC title