Abstract: An optical unit that includes a lens and a frame that is configured to support the lens; wherein the lens has a coefficient of thermal expansion (CTE) of a first value; wherein the frame has a CTE of a second value; wherein the first value differs from the second value; and wherein at least one of the lens and the frame comprises a flexible interface for compensating for differences between thermal expansions of the lens and of the frame.

Abstract: According to one aspect of the presently disclosed subject there is provided a device configured figured to allow illumination of light towards a tunable filter, each time towards a different portion thereof, and detect the optical response, (e.g., transmission or reflection from the portion that is illuminated with light). By detecting optical response of isolated illuminations towards different portions of the tunable filter each time, the state of the tunable filter at the illuminated portion, e.g. the optical gap between a movable member and a stationary member of the tunable filter, can be determined. By monitoring different portions of the tunable filter, the general state of the tunable filter is determined. For example, the general state of the tunable filter may be determined based on the optical gaps at different portions of the tunable filter while the actuation parameters are maintained unchanged.

Abstract: System and method for narrowing the transmission curves obtained using a spectral imager in which spectral images are acquired using a MEMS Fabri-Perot (FP) tunable filter. A method includes acquiring a first plurality of broad-band spectral images associated with respective MEMS FP etalon states and processing the first plurality of broad-band spectral images into a second plurality of narrow-band spectral images.

Abstract: Tunable MEMS etalon devices comprising: a front mirror and a back mirror, the front and back mirrors separated in an initial pre-stressed un-actuated etalon state by a gap having a pre-stressed un-actuated gap size determined by a back stopper structure in physical contact with the front mirror and back mirrors, the etalon configured to assume at least one actuated state in which the gap has an actuated gap size gap greater than the pre-stressed un-actuated gap size; an anchor structure, a frame structure fixedly coupled to the front mirror at a first surface thereof that faces incoming light, and a flexure structure attached to the anchor structure and to the frame structure but not attached to the front mirror, and a spacer structure separating the anchor structure from the back mirror, and wherein the front mirror and the spacer structure are formed in a same single glass layer.

Abstract: The present disclosure provides, among other aspects, a technique, employed in a system and method, for monitoring a state of a tunable optical filter, typically a MEMS tunable filter such as a Fabry-Perot filter. The technique utilizes application of an actuation voltage signal characterized by a first component configured for causing a movement of a movable optical member of the tunable filter and a second component configured for being responsive for each given state of the tunable filter, i.e each optical gap results in a different response of the second component. The response of the second component to the state of the tunable filter, i.e. its variation profile from the original applied second component of the voltage signal is being indicative of the state of the tunable filter.

Abstract: An optical device that may include an enclosure that comprises a first element, a second element; wherein the first element and the second element are at least partially transparent; a movable element that is configured to move within an internal space defined by the enclosure; and wherein the enclosure is sealed and is configured to maintain a pressure difference between a pressure level that exists within the internal space and an ambient pressure level.

Abstract: An optical unit that includes a lens and a frame that is configured to support the lens; wherein the lens has a coefficient of thermal expansion (CTE) of a first value; wherein the frame has a CTE of a second value; wherein the first value differs from the second value; and wherein at least one of the lens and the frame comprises a flexible interface for compensating for differences between thermal expansions of the lens and of the frame.

Abstract: System and method for narrowing the transmission curves obtained using a spectral imager in which spectral images are acquired using a MEMS Fabri-Perot (FP) tunable filter. A method includes acquiring a first plurality of broad-band spectral images associated with respective MEMS FP etalon states and processing the first plurality of broad-band spectral images into a second plurality of narrow-band spectral images.

Abstract: Imaging systems and methods for imaging using the same color or monochromatic image sensor, wherein imaging can be switched between at least two imaging modes, for example between a visible imaging mode and an IR imaging mode, without moving any system component from a given position in an optical path between an imaged object and the image sensor. In an example, a system includes an image sensor, a tunable spectral filter and a multi-bandpass filter, the tunable spectral filter and the multi-bandpass filter arranged in a common optical path between an object and the image sensor, and a controller configured and operable to position the tunable spectral filter in a plurality of operation states related to a plurality of imaging modes.

Abstract: The present invention provides a crystalline halobetasol propionate selected from the group consisting of halobetasol propionate having crystalline Form I characterized by power X-ray diffraction peak positions and intensities as set forth in Table 1 herein, halobetasol propionate having crystalline Form II characterized by power X-ray diffraction peak positions and intensities as set forth in Table 2 herein, halobetasol propionate having crystalline Form III characterized by power X-ray diffraction peak positions and intensities as set forth in Table 3 herein, halobetasol propionate having crystalline Form IV characterized by power X-ray diffraction peak positions and intensities as set forth in Table 4 herein, halobetasol propionate having crystalline Form V characterized by power X-ray diffraction peak positions and intensities as set forth in Table 5 herein, and halobetasol propionate having crystalline Form VI characterized by power X-ray diffraction peak positions and intensities as set forth in Table 6

Abstract: The present invention provides a crystalline halobetasol propionate selected from the group consisting of halobetasol propionate having crystalline Form I characterized by power X-ray diffraction peak positions and intensities as set forth in Table 1 herein, halobetasol propionate having crystalline Form II characterized by power X-ray diffraction peak positions and intensities as set forth in Table 2 herein, halobetasol propionate having crystalline Form III characterized by power X-ray diffraction peak positions and intensities as set forth in Table 3 herein, halobetasol propionate having crystalline Form IV characterized by power X-ray diffraction peak positions and intensities as set forth in Table 4 herein, halobetasol propionate having crystalline Form V characterized by power X-ray diffraction peak positions and intensities as set forth in Table 5 herein, and halobetasol propionate having crystalline Form VI characterized by power X-ray diffraction peak positions and intensities as set forth in Table 6

Abstract: The present invention provides a crystalline halobetasol propionate selected from the group consisting of halobetasol propionate having crystalline Form I characterized by power X-ray diffraction peak positions and intensities as set forth in Table 1 herein, halobetasol propionate having crystalline Form II characterized by power X-ray diffraction peak positions and intensities as set forth in Table 2 herein, halobetasol propionate having crystalline Form III characterized by power X-ray diffraction peak positions and intensities as set forth in Table 3 herein, halobetasol propionate having crystalline Form IV characterized by power X-ray diffraction peak positions and intensities as set forth in Table 4 herein, halobetasol propionate having crystalline Form V characterized by power X-ray diffraction peak positions and intensities as set forth in Table 5 herein, and halobetasol propionate having crystalline Form VI characterized by power X-ray diffraction peak positions and intensities as set forth in Table 6