We present the optomechanical design of a polarimeter to be used with the SCUBA-2 camera at the James-Clerk-Maxwell Telescope. The polarimeter, built to study polarized sub-millimeter radiations, has a clear aperture of 269 mm
and is composed of three optical elements: a calibration polarizer, a half wave plate rotating at a speed of up to5 Hz, and
an analyzer polarizer. All three elements can be placed in and out of the beam, depending on the telescope's observation
mode.
The use of uncooled infrared (IR) imaging technology in Thermal Weapon Sight (TWS) systems produces a unique tool
that perfectly fulfills the all-weather, day-and-night vision demands in modern battlefields by significantly increasing the
effectiveness and survivability of a dismounted soldier. The main advantage of IR imaging is that no illumination is
required; therefore, observation can be accomplished in a passive mode. It is particularly well adapted for target
detection even through smoke, dust, fog, haze, and other battlefield obscurants. In collaboration with the Defense
Research and Development Canada (DRDC Valcartier), INO engineering team developed, produced, and tested a rugged
thermal weapon sight. An infrared channel provides for human detection at 800m and recognition at 200m. Technical
system requirements included very low overall weight as well as the need to be field-deployable and user-friendly in
harsh conditions. This paper describes the optomechanical design and focuses on the catadioptric-based system
integration. The system requirements forced the optomechanical engineers to minimize weight while maintaining a
sufficient level of rigidity in order to keep the tight optical tolerances. The optical system's main features are: a precision
manual focus, a watertight vibration insulated front lens, a bolometer and two gold coated aluminum mirrors. Finite
element analyses using ANSYS were performed to validate the subsystems performance. Some of the finite element
computations were validated using different laboratory setups.
A polarimeter is built to be used with the SCUBA-2 camera of the James Clerk Maxwell Telescope to study polarized sub-millimeter radiations. We simulated the effect of the polarimeter on image quality and polarization measurements.
A rugged lightweight thermal weapon sight (TWS) prototype was developed at INO in collaboration with
DRDC-Valcartier. This TWS model is based on uncooled bolometer technology, ultralight catadioptric
optics, ruggedized mechanics and electronics, and extensive onboard processing capabilities.
The TWS prototype operates in a single 8-12 μm infrared (IR) band. It is equipped with a unique
lightweight athermalized catadioptric objective and a bolometric IR imager with an INO focal plane array
(FPA). Microscan technology allows the use of a 160 x 120 pixel FPA with a pitch of 50 μm to achieve a
320 × 240 pixel resolution image thereby avoiding the size (larger optics) and cost (expensive IR optical
components) penalties associated with the use of larger format arrays. The TWS is equipped with a
miniature shutter for automatic offset calibration. Based on the operation of the FPA at 100 frames per
second (fps), real-time imaging with 320 x 240 pixel resolution at 25 fps is available. This TWS is also
equipped with a high resolution (857 x 600 pixels) OLED color microdisplay and an integrated wireless
digital RF link. The sight has an adjustable and selectable electronic reticule or crosshair (five possible
reticules) and a manual focus from 5 m to infinity standoff distance. Processing capabilities are added to
introduce specific functionalities such as image inversion (black hot and white hot), image enhancement,
and pixel smoothing. This TWS prototype is very lightweight (~ 1100 grams) and compact (volume of 93
cubic inches). It offers human size target detection at 800 m and recognition at 200 m (Johnson criteria).
With 6 Li AA batteries, it operates continuously for 5 hours and 20 minutes at room temperature. It can
operate over the temperature range of -30oC to +40oC and its housing is completely sealed. The TWS is
adapted to weaver or Picatinny rail mounting. The overall design of the TWS prototype is based on
feedbacks of users to achieve improved user-friendly (e.g. no pull-down menus and no electronic focusing)
and ergonomic (e.g. locations of buttons) features.
A dual band thermal/visible weapon sight (TVWS) prototype was developed by INO in collaboration with
DRDC Valcartier. The TVWS operates in the 8-12 μm infrared (IR) and 300-900 nm visible wavebands for
enhanced vision capabilities in day and night operations. It is equipped with lightweight athermalized
coaxial catadioptric objectives, a bolometric IR imager operating in a microscan mode providing an
effective resolution of 320 x 240 pixels and a visible image intensifier of 768 x 493 pixels. The TVWS is
equipped with a miniature shutter for automatic offset calibration. Real-time imaging at 30 fps is available.
Both the visible and IR images can be toggled with a single touch button and displayed on an integrated
color micro liquid crystal display (LCD). The TVWS also has a standard video output via a coaxial
connector. An integrated wireless analog RF link can be used to send images to a remote command control. The sight has an adjustable electronic crosshair and two manual focuses from 25 m to infinity. On-board
processing capabilities were added to introduce specific functionalities such as image polarity inversion
(black hot/white hot) and image enhancement. This TVWS model is also very lightweight (~ 1900 grams)
and compact (volume of 142 cubic inches). It offers human size target detection at 800 m and recognition at
200 m (Johnson criteria) with the IR waveband while offering the human recognition at up to 800 m with
the visible waveband. The TVWS is adapted for weaver or Picatinny rail mounting.
A fast (F/1.55) and wide-angle refractive camera objective has been developed to work with a large-size CCD on the focal plane of the spectrograph of Mont Megantique telescope for large spectral coverage from UV to VIS and up to NIR. The novel camera objective has been designed and optimized with three different glass combinations in order to have higher throughputs for large spectral coverage, especially in UV region. The tolerance analysis of the camera objective is given in the paper. The final opto-mechanical design of the objective is discussed with the consideration of the manufacturing tolerance in the optical and mechanical parts, as given in this paper. The used components have been minimized to reduce the light inherent lost. The optical testing results displayed the good optical performance of the camera with the required resolution for the whole FOV, as predicted by the optical simulation and computation. The broadband AR coating, enhanced on UV region, have been used on each surface of the lenses in the optical system.
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