Abstract: The present techniques provide methods and systems for recording micro-holograms on a holographic disk using a plurality of counter-propagating light beams in parallel. The parallel counter-propagating light beams overlap to form interference patterns on a data layer and over multiple data tracks in the holographic disk. Rotating the disk enables the parallel recording of micro-holograms over multiple data tracks, thus reducing recording time. Further, the illumination pattern may include illuminated spots and non-illuminated regions, such that each illumination spot may cover a relatively small fraction of the data layer plane, possibly controlling the depth spread of the recorded micro-hologram. In some embodiments, data in the parallel signal beams may be retrieved from a master holographic disk or may be modulated into the parallel signal beams.

Abstract: The present techniques provide techniques for outputting counter-propagating parallel light waves to pre-record a holographic data disk. The parallel light waves are transmitted through a holographic system via a fiber optic bundle including a plurality of polarization-maintaining (PM) optical fibers. Each of the PM optical fibers in the fiber optic bundle may have one or more of a different wavelength, a different coherence length, and a different polarization orientation to reduce crosstalk in the disk. Furthermore, the fiber optic bundle array is rotated to produce interference spots indicative of micro-holograms according to the data track pitch of the holographic disk over which the fiber optic bundle is outputting the light waves.

Abstract: The present techniques provide methods and systems for controlling the recording of micro-holograms using multiple counter-propagating light beams over multiple data tracks of a holographic disk. Imperfections in a holographic disk or movement of the disk during a recording process may cause signal beams to deviate from target data tracks. In some embodiments, a tracking beam is directed to a reference layer in the disk. Deviation of the reference beam from a target groove in the reference layer may be indicative of tracking errors. A detector may detect reflections of the tracking beam and generate an error signal in response to detected tracking errors. Servo-mechanical devices may actuate (e.g., radially, tangentially, or axially translate, rotate, and/or tilt) one or more optical components through which the counter-propagating light beams are emitted to compensate for tracking errors.

Abstract: This invention relates to a type of solar energy photo-voltaic power generation equipment that can automatically track the sun. This device includes a pedestal installed on a mounting platform. On the pedestal, a main support frame is provided. On the support frame, a solar cell panel platform is provided. On this platform, a solar energy photo-voltaic assembly is installed. The pedestal is connected to the mounting platform and can rotate relative to the mounting platform. On the pedestal, a circumferentially driven planet reduction gear is installed. On the main support frame, a platform elevation angle adjustment lifter is installed. The end of the telescopic link on the lifter is hinged to the solar cell panel platform. The circumferentially driven planet reduction gear and platform elevation angle adjustment lifter are connected to an electric control device.

Abstract: Macroscopic and microscopic samples are imaged through a spectral filter operable into the short wave infrared, e.g., to approximately 3200 nm. The sample is illuminated for reflective, transmissive, fluorescent and/or Raman imaging by a laser or metal-halide arc beam. The filter has tunable birefringent retarders distributed rotationally and stacked in stages leading up to a selection polarizer. Image forming optics and CCD cameras collect the luminance of each pixel in the spatially resolved image, at multiple wavelengths to which the filter is tuned successively. The filter stages have comb shaped transmission characteristics. Two filter stages with distinctly different characteristics can be cascaded, one or both being tunable. The combined transmission characteristic has narrow passbands where the bandpass peaks of the stages coincide and wide free spectral range where the peaks do not coincide.

Abstract: A wide angle hybrid refractive-diffractive endoscope objective is provided. The objective comprises a negative meniscus lens having a first surface and a second surface; a stop adjacent to the negative meniscus lens; a positive lens adjacent to the negative lens and having a first surface and a second surface; and a hybrid refractive-diffractive element adjacent to the positive lens and having a first surface and a second surface, wherein one of the first surface, or the second surface comprises a diffractive surface, wherein the objective has an effective focal length in a range from about 0.8 mm to about 1.6 mm.

Abstract: A wide angle hybrid refractive-diffractive endoscope objective is provided. The objective comprises a negative meniscus lens having a first surface and a second surface; a stop adjacent to the negative meniscus lens; a positive lens adjacent to the negative lens and having a first surface and a second surface; and a hybrid refractive-diffractive element adjacent to the positive lens and having a first surface and a second surface, wherein one of the first surface, or the second surface comprises a diffractive surface, wherein the objective has an effective focal length in a range from about 0.8 mm to about 1.6 mm.

Abstract: A wavelength discriminating optical filter has birefringent retarders stacked between polarizing filters, in relative rotational orientations causing passband wavelengths to emerge in a polarization state aligned to a second such polarizing filter, for transmission, whereas wavelengths at orthogonal polarization states are blocked. The second polarizing filter can be a wiregrid type that reflects the blocked orthogonal component backwards along the light signal propagation path. Internal reflections are minimized while obtaining a high transmission ratio and high discrimination for the passband wavelengths, by pairing a zero-degree reflective polarizer as the second or selection polarizer, with a preceding non-zero-degree reflective polarizer. The non-zero-degree reflective polarizer can absorb the blocked orthogonal polarization components, for example using an oriented dichroic material, or a polarizing cube or the like can be provided to divert the blocked polarization component.

Abstract: Disclosed are systems for intraoperative nerve imaging using compact high collection power imaging devices for fluorescence and white light imaging of myelin basic protein (MBP) nerve imaging agents during open and minimally invasive surgery.

Abstract: A spectral filter is adapted for use in a receiver, for example in a short range submarine laser signal path, wherein the relative orientations of the receiver is such that the signal may appear diffusely or at an unknown point in a wide external field of view around an optical axis of the receiver. A narrow band spectral filter in the receiver has cascaded stages of tunable retarders with includes multi-conjugate stages that tolerate light that is oblique to normal, up to a diverging internal field of view angle up to about 10°. A fisheye lens assembly refracts incoming light from a wider external field of 170° or more and directs the light into the filter over the narrow internal field of view.

Abstract: An endoscope objective lens for collecting combined bright field (white light) and fluorescence images includes a negative lens group, a stop, and a positive lens group. The lens has a combination of large entrance pupil diameter (?0.4 mm) for efficiently collecting weak fluorescence light, large ratio between the entrance pupil diameter and the maximum outside diameter (Dentrance/Dmax larger than 0.2), large field of view (FFOV?120°) and favorably corrected spherical, lateral chromatic and Petzval field curvature for both visible and near infrared wavelengths.

Abstract: A patch panel assembly includes: a patch panel having a pair of arms fixed relative to each other, the arms forming an obtuse angle, each of the arms including a plurality of mounting locations for telecommunications connectors, with a vertex of the obtuse angle extending in a forward direction, the patch panel further comprising a plurality of telecommunication connectors mounted in the mounting locations; and a display module removably mounted to the patch panel, the display module having a body and a front-facing display surface, the display surface being positioned forwardly of the vertex of the obtuse angle. In this configuration, the removable display module can provide additional display area for annotations regarding the connectivity of the patch panel, and can do so with the attendant advantages of a removable display.

Abstract: An endoscope objective lens for collecting combined bright field (white light) and fluorescence images includes a negative lens group, a stop, and a positive lens group. The lens has a combination of large entrance pupil diameter (?0.4 mm) for efficiently collecting weak fluorescence light, large ratio between the entrance pupil diameter and the maximum outside diameter (Dentrance/Dmax larger than 0.2), large field of view (FFOV?120°) and favorably corrected spherical, lateral chromatic and Petzval field curvature for both visible and near infrared wavelengths.

Abstract: An optical comb filter has polarizers placed before and after two or more birefringent elements, each having a fixed retarder and an aligned tunable liquid crystal. The birefringent elements are equal in birefringence and thickness and are tuned in unison. As few as two birefringent elements are provided, thereby minimizing transitions where infrared absorption occurs. The birefringent elements are in a symmetrical array of rotational angles, encompassing 90° of span in a bandpass configuration where the polarizers are parallel. Polarization components from the input polarizer or a given birefringent element are coupled in unequal proportions to the fast and slow axes of the next birefringent element, by using a relative angle that is distinctly different from 45°. The filter is tolerant of rotational alignment errors. A two element filter uses angles of 22.5 and 67.5°; a three element version has 12.5, 45 and 77.5°; and a four element filter has 7.5, 29.5, 60.5 and 82.5°; all these angles being ±5°.

Abstract: An optical comb filter has polarizers placed before and after two or more birefringent elements, each having a fixed retarder and an aligned tunable liquid crystal. The birefringent elements are equal in birefringence and thickness and are tuned in unison. Wavelength-dependent polarization state changes are contributed by retardation in unequal proportions on the fast and slow axes of the successive birefringent elements. The filter is tolerant of rotational alignment errors. A two element filter uses angles of 22.5 and 67.5°; a three element version has 12.5, 45 and 77.5°; and a four element filter has 7.5, 29.5, 60.5 and 82.5°; all these angles being ±5°.

Abstract: The disclosure generally relates to a multimode imaging apparatus for simultaneously obtaining multiple wavelength-discriminative spectral images of a sample.

Abstract: An optical wavelength filter uses birefringence and polarization to discriminate and block a wavelength stop band. Birefringent elements, each having a fixed retarder and a liquid crystal, are placed along the signal path with the fast and slow axes in each pair being aligned and rotationally displaced from other pairs. The birefringence parts are arranged by their thickness, birefringence and progressive rotational orientation so that each pair contributes to achieving a specific polarization state for specific periodic wavelength discrimination bands. A selection polarizer at the output blocks bands that have this polarization state. The birefringence elements are tuned in a coordinated manner and thereby to select one or more wavelengths as the band stop discrimination band.

Abstract: A hyper-spectral imaging filter has serial stages along an optical signal path with angularly distributed birefringent retarders and polarizers forming interference filters. The retarders can include tunable birefringent elements such as liquid crystals controlled in unison, fixed retarders and/or combined tunable and fixed birefringences. Distinctly different periodic transmission spectra are provided by different filter stages, each having multiple retarders, in particular with some stages having broad bandpass peaks at wide spectral spacing and other stages have very narrow closely spaced peaks. The respective spectra include at least one tunably selectable band at which the transmission spectra of the filter stages coincide, whereby the salutary narrow bandpass and wide spectral spacing ranges of different stages apply together, resulting in a high finesse wavelength filter suitable for spectral imaging.

Abstract: The disclosure generally relates to a multimode imaging apparatus for simultaneously obtaining multiple wavelength-discriminative spectral images of a sample.

Abstract: An optical comb filter has polarizers placed before and after two or more birefringent elements, each having a fixed retarder and an aligned tunable liquid crystal. The birefringent elements are equal in birefringence and thickness and are tuned in unison. As few as two birefringent elements are provided, thereby minimizing transitions where infrared absorption occurs. The birefringent elements are in a symmetrical array of rotational angles, encompassing 90° of span in a bandpass configuration where the polarizers are parallel. Polarization components from the input polarizer or a given birefringent element are coupled in unequal proportions to the fast and slow axes of the next birefringent element, by using a relative angle that is distinctly different from 45°. The filter is tolerant of rotational alignment errors. A two element filter uses angles of 22.5 and 67.5°; a three element version has 12.5, 45 and 77.5°; and a four element filter has 7.5, 29.5, 60.5 and 82.5°; all these angles being ±5°.