Abstract: Laser radar systems include a pentaprism configured to scan a measurement beam with respect to a target surface. A focusing optical assembly includes a corner cube that is used to adjust measurement beam focus. Target distance is estimated based on heterodyne frequencies between a return beam and a local oscillator beam. The local oscillator beam is configured to propagate to and from the focusing optical assembly before mixing with the return beam. In some examples, heterodyne frequencies are calibrated with respect to target distance using a Fabry-Perot interferometer having mirrors fixed to a lithium aluminosilicate glass-ceramic tube.

Abstract: An optical delay between a first fiber and a second fiber is temperature compensated by combining fibers with different thermal path length changes. In some examples, fibers with different buffer coatings exhibit different path length changes per unit length and temperature. Combining such fibers in a fiber array provides a path length difference that is substantially independent of temperature.

Abstract: Laser radar systems include a pentaprism configured to scan a measurement beam with respect to a target surface. A focusing optical assembly includes a corner cube that is used to adjust measurement beam focus. Target distance is estimated based on heterodyne frequencies between a return beam and a local oscillator beam. The local oscillator beam is configured to propagate to and from the focusing optical assembly before mixing with the return beam. In some examples, heterodyne frequencies are calibrated with respect to target distance using a Fabry-Perot interferometer having mirrors fixed to a lithium aluminosilicate glass-ceramic tube.

Abstract: Laser radar systems include a pentaprism configured to scan a measurement beam with respect to a target surface. A focusing optical assembly includes a corner cube that is used to adjust measurement beam focus. Target distance is estimated based on heterodyne frequencies between a return beam and a local oscillator beam. The local oscillator beam is configured to propagate to and from the focusing optical assembly before mixing with the return beam. In some examples, heterodyne frequencies are calibrated with respect to target distance using a Fabry-Perot interferometer having mirrors fixed to a lithium aluminosilicate glass-ceramic tube.

Abstract: Laser radar systems include a pentaprism configured to scan a measurement beam with respect to a target surface. A focusing optical assembly includes a corner cube that is used to adjust measurement beam focus. Target distance is estimated based on heterodyne frequencies between a return beam and a local oscillator beam. The local oscillator beam is configured to propagate to and from the focusing optical assembly before mixing with the return beam. In some examples, heterodyne frequencies are calibrated with respect to target distance using a Fabry-Perot interferometer having mirrors fixed to a lithium aluminosilicate glass-ceramic tube.

Abstract: Laser radar systems include a pentaprism configured to scan a measurement beam with respect to a target surface. A focusing optical assembly includes a corner cube that is used to adjust measurement beam focus. Target distance is estimated based on heterodyne frequencies between a return beam and a local oscillator beam. The local oscillator beam is configured to propagate to and from the focusing optical assembly before mixing with the return beam. In some examples, heterodyne frequencies are calibrated with respect to target distance using a Fabry-Perot interferometer having mirrors fixed to a lithium aluminosilicate glass-ceramic tube.

Abstract: Laser radar systems include a pentaprism configured to scan a measurement beam with respect to a target surface. A focusing optical assembly includes a corner cube that is used to adjust measurement beam focus. Target distance is estimated based on heterodyne frequencies between a return beam and a local oscillator beam. The local oscillator beam is configured to propagate to and from the focusing optical assembly before mixing with the return beam. In some examples, heterodyne frequencies are calibrated with respect to target distance using a Fabry-Perot interferometer having mirrors fixed to a lithium aluminosilicate glass-ceramic tube.

Abstract: Laser radar systems include a pentaprism configured to scan a measurement beam with respect to a target surface. A focusing optical assembly includes a corner cube that is used to adjust measurement beam focus. Target distance is estimated based on heterodyne frequencies between a return beam and a local oscillator beam. The local oscillator beam is configured to propagate to and from the focusing optical assembly before mixing with the return beam. In some examples, heterodyne frequencies are calibrated with respect to target distance using a Fabry-Perot interferometer having mirrors fixed to a lithium aluminosilicate glass-ceramic tube.

Abstract: An optical delay between a first fiber and a second fiber is temperature compensated by combining fibers with different thermal path length changes. In some examples, fibers with different buffer coatings exhibit different path length changes per unit length and temperature. Combining such fibers in a fiber array provides a path length difference that is substantially independent of temperature.

Abstract: Laser radar systems include a pentaprism configured to scan a measurement beam with respect to a target surface. A focusing optical assembly includes a corner cube that is used to adjust measurement beam focus. Target distance is estimated based on heterodyne frequencies between a return beam and a local oscillator beam. The local oscillator beam is configured to propagate to and from the focusing optical assembly before mixing with the return beam. In some examples, heterodyne frequencies are calibrated with respect to target distance using a Fabry-Perot interferometer having mirrors fixed to a lithium aluminosilicate glass-ceramic tube.

Abstract: Laser radar systems include a pentaprism configured to scan a measurement beam with respect to a target surface. A focusing optical assembly includes a corner cube that is used to adjust measurement beam focus. Target distance is estimated based on heterodyne frequencies between a return beam and a local oscillator beam. The local oscillator beam is configured to propagate to and from the focusing optical assembly before mixing with the return beam. In some examples, heterodyne frequencies are calibrated with respect to target distance using a Fabry-Perot interferometer having mirrors fixed to a lithium aluminosilicate glass-ceramic tube.

Abstract: A system for measurement of a distance to a target. Light is emitted from a multi-mode laser and coupled to a sensor assembly. A portion of the light at the sensor assembly is reflected back into the fiber optic cable from which it came. The other portion of the light from the sensor assembly is projected towards the target. Light is reflected from the target and also connected into the optical cable as a target beam. The target beam and the reference beam then are connected through a path of variable length. When the target beam and the reference beam interface with one another, the path length is determined to be equal to the length to the target.

Abstract: A precision optical distance measuring device utilizes coherent optical detection for extreme precision, and polarization preserving fiber to enable its use in limited access environments. A laser diode provides a linearly polarized source light beam which is directed to a polarizing beam splitter. The source beam passes through the beam splitter and is focused by a lens into a polarization preserving fiber where it travels along one optical axis toward a probe head disposed at the target location. In the probe head, the source beam is focused by a lens onto the target. After focusing, the source beam is passed through a quarter-wave plate. The interface between ambient air and the target-side of the quarter-wave plate reflects a local oscillator beam back through the quarter-wave plate. Meanwhile, the source beam is reflected from the target as a return beam.

Abstract: A laser proximity sensor for a projectile includes a laser diode having front and rear facets. The diode generates a main laser signal and directs a first portion thereof out of the front facet as a source beam. Focusing means focuses the source beam on a target, and focuses the return beam reflected from the target into the laser diode through the front facet. The laser diode receives the return light beam, provides it with a positive gain, mixes it with the main laser signal, and guides it out the rear facet as a mixed beam. A detection focusing device focuses the mixed beam onto a PIN detector. The PIN detector coherently detects the mixed beam and provides an output signal having a perturbation where the target enters the focal field of the focusing optics. A processor detects the output signal from the PIN detector and may activate a fuse on the projectile.