Infrared imaging device having a shutter
View Patent ↗A shutter assembly may be provided for an infrared imaging module to selectively block external infrared radiation from reaching infrared sensors of the infrared imaging module. For example, the shutter assembly may comprise a paddle situated external to an optical element (e.g., lens) and adapted to be selectively moved by an actuator to substantially block external infrared radiation from entering the optical element. The shutter assembly may be stacked relative to a housing of the infrared imaging module without excessively increasing the overall profile of the infrared imaging module. A substantially reflective low emissivity interior surface may be provided on the paddle to reflect infrared radiation originating from an infrared sensor assembly of the infrared imaging module back to the infrared sensor assembly.
1. A system comprising:
an infrared imaging module comprising:
an infrared sensor assembly having infrared sensors and adapted to capture image frames;
a housing substantially enclosing the infrared sensor assembly and having at least one conductive trace providing an electrical connection disposed on and extending along at least a portion of an exterior surface of the housing; and
a shutter assembly external to and coupled to the housing, the shutter assembly comprising:
a paddle adapted to selectively block external infrared radiation from reaching the infrared sensors,
an actuator adapted to selectively move the paddle in response to a control signal to block external infrared radiation from reaching the infrared sensors, and
an electrical contact adapted to interface with the conductive trace on the exterior surface of the housing to receive the control signal while the shutter assembly is coupled to the housing.
2. The system of claim 1 , wherein:
the infrared sensor assembly further comprises a temperature sensor adapted to detect a temperature associated with the infrared sensor assembly;
the infrared imaging module further comprises an optical element adapted to pass infrared radiation through to the infrared sensors;
the paddle is disposed external to the optical element and adapted to selectively block external infrared radiation from reaching the optical element; and
the paddle comprises a substantially reflective surface adapted to reflect infrared radiation originating from the infrared sensor assembly back to the infrared sensor assembly while the paddle is in a closed position to calibrate the infrared sensors using the reflected infrared radiation and the detected temperature.
3. The system of claim 1 , wherein the infrared imaging module further comprises a temperature sensor adapted to detect a temperature associated with the paddle.
4. The system of claim 3 , wherein the temperature sensor is provided in or on the paddle.
5. The system of claim 4 , wherein the shutter assembly comprises an electrical wire disposed on the paddle and electrically connected to the temperature sensor.
6. The system of claim 4 , wherein the paddle is a molded interconnect device (MID) and comprises a conductive trace formed on a surface of the paddle and electrically connected to the temperature sensor.
7. The system of claim 4 , wherein:
the paddle is made from a silicon substrate and comprises:
at least one surface that is doped to decrease transmissivity of infrared radiation therethrough, and
an electrical wire fabricated using a semiconductor fabrication process and electrically connected to the temperature sensor; and
the temperature sensor is a semiconductor device fabricated on the paddle.
8. The system of claim 1 , wherein the shutter assembly comprises a body carrying the paddle.
9. The system of claim 8 , wherein:
the housing is a molded interconnect device (MID) and the conductive trace extends from the exterior surface of the housing to an interior surface of the housing and/or to a location embedded in the housing; and
the conductive trace is adapted to transmit the control signal to the actuator.
10. The system of claim 9 , wherein the electrical contact comprises a spring contact adapted to bias against the conductive trace to interface therewith.
11. The system of claim 8 , wherein the infrared imaging module further comprises:
a temperature sensor disposed on an interior surface of the housing;
a thermal conductor adapted to thermally couple at least a portion of the shutter assembly body and at least a portion of the housing so as to communicate thermal energy between the shutter assembly body and the temperature sensor; and
a processor configured to generate a combined image comprising:
a radiometric component of at least one of the infrared image frames encoded into a chrominance component of the combined image, and
luminance and/or chrominance component of at least one non-thermal image encoded into a luminance component of the combined image.
12. The system of claim 8 , wherein the infrared imaging module further comprises a temperature sensor disposed in or on the shutter assembly body and adapted to detect a temperature associated with the paddle.
13. The system of claim 8 , wherein:
the infrared imaging module further comprises a lens barrel coupled to and at least partially within the housing;
the lens barrel substantially encloses an optical element adapted to pass infrared radiation through to the infrared sensors;
the shutter assembly body comprises a recess shaped to receive at least a portion of the lens barrel and/or the housing; and
the shutter assembly body is stacked relative to the housing by receiving at least a portion of the housing and/or the lens barrel in the recess.
14. A method comprising:
selectively moving a paddle to block external infrared radiation from reaching infrared sensors of an infrared sensor assembly substantially enclosed in a housing having at least one conductive trace providing an electrical connection disposed on and extending along at least a portion of an exterior surface of the housing;
capturing, using the infrared sensor assembly, image frames of infrared radiation;
wherein the paddle is selectively moved by an actuator in response to a control signal;
wherein the paddle and the actuator are part of a shutter assembly external to and coupled to the housing, the shutter assembly having an electrical contact adapted to interface with the conductive trace on the exterior surface of the housing to receive the control signal while the shutter assembly is coupled to the housing;
wherein the shutter assembly and the housing are part of an infrared imaging module.
15. The method of claim 14 , further comprising:
prior to the capturing, reflecting infrared radiation originating from the infrared sensor assembly back to the infrared sensor assembly by a substantially reflective surface of the paddle while the paddle is in a closed position, wherein the captured infrared radiation is the reflected infrared radiation;
detecting a temperature associated with the infrared sensor assembly; and
calibrating the infrared sensors using the captured infrared radiation and the detected temperature.
16. The method of claim 14 , further comprising detecting a temperature associated with the paddle using a temperature sensor of the infrared imaging module.
17. The method of claim 16 , wherein the temperature sensor is provided in or on the paddle to detect the temperature.
18. The method of claim 17 , wherein the detecting the temperature comprises transmitting an electrical signal indicative of the temperature via an electrical wire disposed on the paddle and electrically connected to the temperature sensor.
19. The method of claim 17 , wherein:
the paddle is a molded interconnect device (MID); and
the detecting the temperature comprises transmitting an electrical signal indicative of the temperature via a conductive trace formed on a surface of the paddle and electrically connected to the temperature sensor.
20. The method of claim 17 , wherein:
the paddle is made from a silicon substrate and comprises at least one surface that is doped to decrease transmissivity of infrared radiation therethrough;
the temperature sensor is a semiconductor device fabricated on the paddle; and
the detecting the temperature comprises transmitting an electrical signal indicative of the temperature via an electrical wire fabricated on the paddle using a semiconductor fabrication process and electrically connected to the temperature sensor.
21. The method of claim 14 , wherein:
the housing is a molded interconnect device (MID) and the conductive trace extends from the exterior surface of the housing to an interior surface of the housing and/or to a location embedded in the housing; and
the method further comprises transmitting the control signal to the actuator via the conductive trace.
22. The method of claim 21 , wherein:
the shutter assembly comprises:
a body carrying the actuator, and
the electrical contact comprising a spring contact adapted to bias against the conductive trace to interface therewith.
23. The method of claim 14 , wherein the shutter assembly comprises a body carrying the paddle,
the method further comprises:
transferring, via a thermal conductor thermally coupling at least a portion of the shutter assembly body and at least a portion of the housing, thermal energy between the shutter assembly body and the housing,
detecting a temperature associated with the paddle using a temperature sensor disposed on an interior surface of the housing, and
generating a combined image comprising:
a radiometric component of at least one of the infrared image frames encoded into a chrominance component of the combined image, and
a luminance and/or chrominance component of at least one non-thermal image encoded into a luminance component of the combined image.
24. The method of claim 14 , wherein the shutter assembly comprises a body carrying the paddle, the method further comprising detecting a temperature associated with the paddle using a temperature sensor disposed in or on the shutter assembly body.