Abstract: A radar system for detecting objects can comprise an RF transmitter that emits RF light and at least one light source that emits visible light in response to the RF light detecting the presence of an object. The system can include a dielectric lens that collects and focuses the RF light. The dielectric lens can also include features that collect and scatter the visible light.

Abstract: A radar system for detecting objects can comprise an RF transmitter that emits RF light and at least one light source that emits visible light in response to the RF light detecting the presence of an object. The system can include a dielectric lens that collects and focuses the RF light. The dielectric lens can also include features that collect and scatter the visible light.

Abstract: An infrared detection device can be used to detect coal mine polar gas. The detection device can include a central processor and a gas pool assembly having a moveable optical window. The moveable optical window can include a stationary pool body and a moveable pool body inserted into the stationary pool body.

Abstract: An infrared detection device can be used to detect coal mine polar gas. The detection device can include a central processor and a gas pool assembly having a moveable optical window. The moveable optical window can include a stationary pool body and a moveable pool body inserted into the stationary pool body.

Abstract: An infrared detection device can be used to detect coal mine polar gas. The detection device can include a central processor and a gas pool assembly having a moveable optical window. The moveable optical window can include a stationary pool body and a moveable pool body inserted into the stationary pool body.

Abstract: An infrared detection device can be used to detect coal mine polar gas. The detection device can include a central processor and a gas pool assembly having a moveable optical window. The moveable optical window can include a stationary pool body and a moveable pool body inserted into the stationary pool body.

Abstract: Multiple signal characteristics representing an entire field of view of an FMCW (FM-CW) sensor are evaluated to determine whether the field of view has changed. Signal characteristics representing the field can be compared to representative signal characteristics obtained from previous scans. At least one signal characteristic representing at least a portion of the scene can be evaluated by comparing the signal characteristic to a dynamic threshold. The dynamic threshold can be redefined after each scan from the statistics of the signal characteristic. The dead zone of a sensor can be reduced by filtering out noise that would otherwise overshadow a signal representing the near-field region of a scene. The noise can be filtered by subtracting a polynomial curve from a time-domain signal representing the scene after fitting the polynomial curve to a representative signal generated based on previous scene scans.

Abstract: Multiple signal characteristics representing an entire field of view of an FMCW (FM-CW) sensor are evaluated to determine whether the field of view has changed. Signal characteristics representing the field can be compared to representative signal characteristics obtained from previous scans. At least one signal characteristic representing at least a portion of the scene can be evaluated by comparing the signal characteristic to a dynamic threshold. The dynamic threshold can be redefined after each scan from the statistics of the signal characteristic. The dead zone of a sensor can be reduced by filtering out noise that would otherwise overshadow a signal representing the near-field region of a scene. The noise can be filtered by subtracting a polynomial curve from a time-domain signal representing the scene after fitting the polynomial curve to a representative signal generated based on previous scene scans.

Abstract: The present disclosure relates to a radar device and technique for detecting the presence of objects located in the near-field of a frequency modulated, continuous wave (FMCW) radar device. The technique includes transmitting and receiving a frequency modulated signal, generating an intermediate frequency signal based on the transmitted and received signals, and analyzing the frequency content of the intermediate frequency signal. The frequency content of the intermediate signal is analyzed without filtering out a carrier signal.

Abstract: A distance sensing system employs an optical triangulation system and a position sensitive device (PSD). The PSD generates a pair of current signals when a target reflects light from a light source back to the surface of the PSD. An automatic power control circuit is used to keep one of the current signals a constant value. The position of the reflected light spot on the PSD is linearly proportional to the other current generated by the PSD according to the formula:Y=C.times.I2Where Y is the spot position and C is a normalization constant. The signal I2 is processed to extract distance information relative to the target.