1000nm 대역 통과 필터

Context: This patent describes a multi-spectral infrared camera system designed to capture images of subjects (such as people or vehicles) through various environmental obscurants. It utilizes a mechanism to switch between different narrow-band filters.

Usage of Filter: The 1000 nm bandpass filter is used as one of several discrete filters mounted on a selectable filter wheel or switching mechanism positioned in the optical path between the lens and the detector. The patent explicitly describes an embodiment containing filters centered at 700 nm, 800 nm, 900 nm, and 1000 nm.

Function: The filter functions to spectrally isolate a narrow slice of the infrared spectrum (approximately 4$\pm$ 20 nm around the 1000 nm center).5 It blocks visible light and other infrared wavelengths that might be scattered by fog, smoke, or windshield glass.

Result: The system achieves enhanced target contrast and visibility. By isolating the 1000 nm wavelength, the camera can "see" details that are invisible to the naked eye or washed out in broadband images, effectively filtering out visual noise and improving detection reliability.

Context: This patent describes a LIDAR system used for autonomous vehicle navigation, which emits laser pulses and detects reflections to measure distance. It focuses on the optical architecture for handling the transmit and receive paths.

Usage of Filter: The bandpass filter is used as a solar background rejection filter placed immediately before the receiver (avalanche photodiode or detector array). It is matched to the specific laser wavelength (in the NIR/SWIR region, such as 1000-1550 nm).

Function: The filter functions to block ambient solar radiation and stray light while allowing the specific narrowband laser return signal to pass through to the detector.

Result: The instrument achieves a high Signal-to-Noise Ratio (SNR). By eliminating the background noise from sunlight (which is broad spectrum), the system can detect faint reflections from distant objects, significantly increasing the effective range and accuracy of the LIDAR data.