Abstract: An apparatus includes a top surface configured to couple to a variable aperture mechanism (VAM), where the top surface has an opening configured to align with an aperture of the VAM. The apparatus also includes a bottom portion configured to couple to a cooled object and a contact portion configured to couple to a strut, where the top surface, bottom portion, and contact portion form a continuous body. The apparatus further includes a plurality of baffles within the continuous body, where each of the baffles has an opening configured to align with the aperture of the VAM. In addition, the apparatus includes a reinforcement ring comprised in or within the continuous body and disposed to be aligned with the strut when the strut is coupled to the continuous body.

Abstract: An apparatus includes a top surface configured to couple to a variable aperture mechanism (VAM), where the top surface has an opening configured to align with an aperture of the VAM. The apparatus also includes a bottom portion configured to couple to a cooled object and a contact portion configured to couple to a strut, where the top surface, bottom portion, and contact portion form a continuous body. The apparatus further includes a plurality of baffles within the continuous body, where each of the baffles has an opening configured to align with the aperture of the VAM. In addition, the apparatus includes a reinforcement ring comprised in or within the continuous body and disposed to be aligned with the strut when the strut is coupled to the continuous body.

Abstract: An Infrared Detector Dewar system includes a housing and an infrared detector. The system also includes one or more strut members coupled on a first end to the housing. The system further includes cold shield coupled to the infrared detector and to a second end of the one or more strut members. The cold shield includes a reinforcement ring aligned with the one or more strut members. The cold shield is formed by forming a support member having disc encased by a support ring. The support member is positioned within a mandrel such that the reinforcement ring is disposed to align with a strut position. The cold shield is then formed by electroplating copper over the mandrel and at least a portion of the support member, and then by removing/dissolving all aforementioned mandrels.

Abstract: An Infrared Detector Dewar system includes a housing and an infrared detector. The system also includes one or more strut members coupled on a first end to the housing. The system further includes cold shield coupled to the infrared detector and to a second end of the one or more strut members. The cold shield includes a reinforcement ring aligned with the one or more strut members. The cold shield is formed by forming a support member having disc encased by a support ring. The support member is positioned within a mandrel such that the reinforcement ring is disposed to align with a strut position. The cold shield is then formed by electroplating copper over the mandrel and at least a portion of the support member, and then by removing/dissolving all aforementioned mandrels.

Abstract: A drive mechanism configured to drive a thermally isolated actuator between two positions. The drive mechanism includes a rotary actuated motor configured to rotatably drive a motor member, and a drive member coupled to the motor member and having a drive arm configured to responsively move from a first position to a second position upon rotation of the motor member. An actuator is responsive to movement of the drive arm moved from the first position to the second position. A drive circuit is configured to generate a pulse width modulated (PWM) drive signal configured to controllably drive the motor, the PWM drive signal having a first duty cycle configured to advance the drive arm from the first position, and having a second duty cycle different than the first duty cycle as the drive arm approaches the second position. The drive signal may be removed before the drive arm engages a hard stop.

Abstract: A shutter assembly comprising a first planar member and a second planar member opposed from one another and forming a sleeve having a cavity therebetween, the sleeve having a pair of side rails adjacent the cavity along sides of the sleeve. A first shutter member having a first end is disposed in the cavity and slidingly disposed along one of the side rails, and a second shutter member having a second end is disposed in the cavity and slidingly disposed along the other side rail. The first end is opposed to the second end and is configured to be selectively advanced towards, and retracted from, the second end so as to define an aperture therebetween having a first shape when disposed in a first position, and wherein the aperture has a second larger shape when the first end is disposed in a second position. The first shutter member and the second shutter member maintain a thermal contact with the side rails and the planar members in all positions.

Abstract: An apparatus includes a first blade configured to be coupled to a first magnet and a second blade configured to be coupled to a second magnet. At least one of the blades has at least one cutout. The apparatus also includes electromagnetic motors configured to generate different electromagnetic fields to (i) cause the magnets to move the blades into a first configuration and (ii) cause the magnets to move the blades into a second configuration. The blades are separated to form a larger aperture in the first configuration, and the at least one cutout in the blades forms a smaller aperture in the second configuration. The apparatus may further include a cover plate and a base plate. The base plate can include an opening that defines the larger aperture and blade stops and stop pins configured to stop movement of the blades.

Abstract: A drive mechanism including a rotary actuated motor configured to rotatably drive a drive arm between a first position to a second position and an actuator responsive to movement of the arm, wherein the actuator is thermally isolated from the arm in both the first position and the second position to create a thermal barrier. The drive arm is configured to engage and advance the actuator between the first position and the second position, while remaining physically spaced from the actuator in the first position and the second position. The drive arm includes a recess such as an opening, wherein the actuator has a member configured to reside in the recess and remain thermally isolated from the arm in both the first position and the second position. In one preferred embodiment, a shutter of an imaging device is positioned in response to the actuator, which shutter remains thermally isolated from the motor and arm. Other devices may be driven as well, such as switches.

Abstract: A device operable in a ultra-high vacuum and in a cryogenic environment. The device has bi-stable solenoid motors configured to drive a shutter assembly defining an aperture having a first shape when the motors are each disposed in the respective first position, and wherein the aperture has a second shape when the motors are each disposed in the respective second position. Actuators responsive to the motors are thermally isolated from the cryogenic shutter assembly except when the motors position the shutter assembly to change a shape of the aperture. The device is suitable for use in FLIR and other thermally sensitive devices.

Abstract: A drive mechanism configured to drive a thermally isolated actuator between two positions. The drive mechanism includes a rotary actuated motor configured to rotatably drive a motor member, and a drive member coupled to the motor member and having a drive arm configured to responsively move from a first position to a second position upon rotation of the motor member. An actuator is responsive to movement of the drive arm moved from the first position to the second position. A drive circuit is configured to generate a pulse width modulated (PWM) drive signal configured to controllably drive the motor, the PWM drive signal having a first duty cycle configured to advance the drive arm from the first position, and having a second duty cycle different than the first duty cycle as the drive arm approaches the second position. The drive signal may be removed before the drive arm engages a hard stop.

Abstract: A drive mechanism including a rotary actuated motor configured to rotatably drive a drive arm between a first position to a second position and an actuator responsive to movement of the arm, wherein the actuator is thermally isolated from the arm in both the first position and the second position to create a thermal barrier. The drive arm is configured to engage and advance the actuator between the first position and the second position, while remaining physically spaced from the actuator in the first position and the second position. The drive arm includes a recess such as an opening, wherein the actuator has a member configured to reside in the recess and remain thermally isolated from the arm in both the first position and the second position. In one preferred embodiment, a shutter of an imaging device is positioned in response to the actuator, which shutter remains thermally isolated from the motor and arm. Other devices may be driven as well, such as switches.

Abstract: A device operable in a ultra-high vacuum and in a cryogenic environment. The device has bi-stable solenoid motors configured to drive a shutter assembly defining an aperture having a first shape when the motors are each disposed in the respective first position, and wherein the aperture has a second shape when the motors are each disposed in the respective second position. Actuators responsive to the motors are thermally isolated from the cryogenic shutter assembly except when the motors position the shutter assembly to change a shape of the aperture. The device is suitable for use in FUR and other thermally sensitive devices.

Abstract: A shutter assembly comprising a first planar member and a second planar member opposed from one another and forming a sleeve having a cavity therebetween, the sleeve having a pair of side rails adjacent the cavity along sides of the sleeve. A first shutter member having a first end is disposed in the cavity and slidingly disposed along one of the side rails, and a second shutter member having a second end is disposed in the cavity and slidingly disposed along the other side rail. The first end is opposed to the second end and is configured to be selectively advanced towards, and retracted from, the second end so as to define an aperture therebetween having a first shape when disposed in a first position, and wherein the aperture has a second larger shape when the first end is disposed in a second position. The first shutter member and the second shutter member maintain a thermal contact with the side rails and the planar members in all positions.

Abstract: An apparatus includes a first blade configured to be coupled to a first magnet and a second blade configured to be coupled to a second magnet. At least one of the blades has at least one cutout. The apparatus also includes electromagnetic motors configured to generate different electromagnetic fields to (i) cause the magnets to move the blades into a first configuration and (ii) cause the magnets to move the blades into a second configuration. The blades are separated to form a larger aperture in the first configuration, and the at least one cutout in the blades forms a smaller aperture in the second configuration. The apparatus may further include a cover plate and a base plate. The base plate can include an opening that defines the larger aperture and blade stops and stop pins configured to stop movement of the blades.

Abstract: According to one embodiment, an optical device includes a variable aperture mechanism configured on a structure having a radiation detector that receives radiation through an aperture of the variable aperture mechanism. The aperture is selectively movable from a first position to a second position in which the aperture has a different size relative to the aperture in the first position. The structure is configured with one or more magnets that function with one or more magnetically permeable members configured on the variable aperture mechanism to hold the variable aperture mechanism in at least one position using a magnetic force between the magnets and magnetically permeable members.

Abstract: According to one embodiment, an optical device includes a variable aperture mechanism configured on a structure having a radiation detector that receives radiation through an aperture of the variable aperture mechanism. The aperture is selectively movable from a first position to a second position in which the aperture has a different size relative to the aperture in the first position. The structure is configured with one or more magnets that function with one or more magnetically permeable members configured on the variable aperture mechanism to hold the variable aperture mechanism in at least one position using a magnetic force between the magnets and magnetically permeable members.

Abstract: Provided is a low friction, self-lubricating sleeve for use with a reciprocating piston in the compressor and/or the expander subsystem of a cryogenic cooler or other compressor type system. The sleeve is bonded to an outer surface of the piston, thereby positioning the sleeve between the piston and an inner wall of a piston cylinder. The sleeve is manufactured using a polyetheretherketone base material, as well as varying percentages of carbon and/or polytetrafluoroethylene fillers. The sleeve may include a dry lubricant such as graphite or molybdenum disulfide, and may extend for all or part of the length of the piston. The sleeve demonstrates negligible wear over thousands of hours of use in the cryogenic cooler, thereby minimizing system gas blow-back and maximizing system efficiency/performance.