Techniques for determining characteristics of a stream of jetted material in a three-dimensional (3D) printer are disclosed. An example 3D printer includes an ejector configured to release molten droplets along a jetting path from the ejector to a build platform. The 3D printer also includes a sensor positioned adjacent to the jetting path and an optical mask positioned adjacent to the jetting path. The optical mask includes a plurality of regions comprising light-blocking regions and light-passing regions. The optical mask is configured to modulate a signal generated by the sensor as the molten droplets travel along the jetting path. The 3D printer also includes a controller to control the 3D printer based on the signal.

A method for contactlessly establishing a temperature of a surface includes determining the temperature measurement values of the plurality of measurement pixels. The method further includes correcting the temperature measurement values by using in each case a pixel-associated temperature drift component. The method further includes at least temporarily suppressing an incidence of infrared radiation onto the infrared detector array using the closure mechanism of the infrared measurement system while temperature measurement values are being determined. The method further includes determining the temperature drift components using the temperature measurement values.

A high speed thermal imaging system includes a thermal imaging camera, the camera including a lens. The housing further includes a front portion and rear portion. The camera and lens are disposed in the housing, which further includes an opening on the front portion. The lens has a field of view through the opening. A rotating shutter disposed in the housing. The rotating shutter may be located between the opening and the optical path of the thermal sensor. The housing may be disposed near a rail track. The lens has a field of view for an object or objects of interest, such as a high speed passing train that includes bearings and brakes of railcar vehicles, (i.e. locomotives, railcars, etc.). The camera may be operable to capture thermal images of the passing rail vehicle wheels including the bearing and brake areas.

Reduces an increase in temperature of the blade member. Comprises: a blade supporting member, disposed forward of a photodetecting sensor that acts as a thermal source, having an opening 1a through which passes light that is to be incident into the photodetecting sensor; a blade member, supported movably on the blade supporting member, for opening and closing the opening; an actuator for driving the blade member open and closed, wherein: wherein the blade supporting member comprises a containing portion 1b, for containing the blade member and the actuator on a front or rear surface that is perpendicular to the optical axis of the opening, and an exposed portion that is arranged in parallel to the containing portion.

A passive infrared (PIR) sensor system, includes a PIR sensor configured to produce an output signal in response to receiving infrared (IR) radiation, an electronic shutter positionable in a field of view (FOV) of the PIR sensor, wherein the electronic shutter includes a liquid crystal (LC) material, wherein the electronic shutter includes a first state providing a first transmissivity of IR radiation through the electronic shutter and a second state providing a second transmissivity of IR radiation through the electronic shutter that is less than the first transmissivity, and a shutter actuator configured to apply an actuation signal to the electronic shutter to actuate the electronic shutter between the first state and the second state.

A passive infrared (PIR) sensor system, includes a PIR sensor configured to produce an output signal in response to receiving infrared (IR) radiation, an electronic shutter positionable in a field of view (FOV) of the PIR sensor, wherein the electronic shutter includes a liquid crystal (LC) material, wherein the electronic shutter includes a first state providing a first transmissivity of IR radiation through the electronic shutter and a second state providing a second transmissivity of IR radiation through the electronic shutter that is less than the first transmissivity, and a shutter actuator configured to apply an actuation signal to the electronic shutter to actuate the electronic shutter between the first state and the second state.

A camera, computer program, and method for determining and displaying temperature rates of change for regions within the camera's field of view. More specifically, the embodiments provide for the continuous, real-time temperature measurement and display of a plurality of objects within the camera's field of view, and further for the real-time processing and display of the temperature rates of change for the region.

A passive infrared (PIR) sensor system, includes a PIR sensor configured to produce an output signal in response to receiving infrared (IR) radiation, an electronic shutter positionable in a field of view (FOV) of the PIR sensor, wherein the electronic shutter includes a liquid crystal (LC) material, wherein the electronic shutter includes a first state providing a first transmissivity of IR radiation through the electronic shutter and a second state providing a second transmissivity of IR radiation through the electronic shutter that is less than the first transmissivity, and a shutter actuator configured to apply an actuation signal to the electronic shutter to actuate the electronic shutter between the first state and the second state.

A passive infrared (PIR) sensor system, includes a PIR sensor configured to produce an output signal in response to receiving infrared (IR) radiation, an electronic shutter positionable in a field of view (FOV) of the PIR sensor, wherein the electronic shutter includes a liquid crystal (LC) material, wherein the electronic shutter includes a first state providing a first transmissivity of IR radiation through the electronic shutter and a second state providing a second transmissivity of IR radiation through the electronic shutter that is less than the first transmissivity, and a shutter actuator configured to apply an actuation signal to the electronic shutter to actuate the electronic shutter between the first state and the second state.

A thermal processing system for performing thermal processing can include a workpiece support plate configured to support a workpiece and heat source(s) configured to heat the workpiece. The thermal processing system can include window(s) having transparent region(s) that are transparent to electromagnetic radiation within a measurement wavelength range and opaque region(s) that are opaque to electromagnetic radiation within a portion of the measurement wavelength range. A temperature measurement system can include a plurality of infrared emitters configured to emit infrared radiation and a plurality of infrared sensors configured to measure infrared radiation within the measurement wavelength range where the transparent region(s) are at least partially within a field of view the infrared sensors. A controller can be configured to perform operations including obtaining transmittance and reflectance measurements associated with the workpiece and determining, based on the measurements, a temperature of the workpiece less than about 600 C.