A device for thermally actuating a deformable mirror includes a monolithic block that includes a mirror plate having a front face forming or configured to support a mirror, a base, and a one-dimensional array of thermally expandable actuators. The thermally expandable actuators mechanically connect a rear face of the mirror plate to the base such that shape, tilt, and/or location of the front face depend on temperature of the thermally expandable actuators. The mirror plate, base, and thermally expandable actuators are defined by slits that span between opposite-facing top and bottom surfaces of the monolithic block. The monolithic block may be made of a metal and may be manufactured at relatively low cost by wire eroding the slits in a metal block, using a wire that passes through the metal block between its top and bottom surfaces.

A device for thermally actuating a deformable mirror includes a monolithic block that includes a mirror plate having a front face forming or configured to support a mirror, a base, and a one-dimensional array of thermally expandable actuators. The thermally expandable actuators mechanically connect a rear face of the mirror plate to the base such that shape, tilt, and/or location of the front face depend on temperature of the thermally expandable actuators. The mirror plate, base, and thermally expandable actuators are defined by slits that span between opposite-facing top and bottom surfaces of the monolithic block. The monolithic block may be made of a metal and may be manufactured at relatively low cost by wire eroding the slits in a metal block, using a wire that passes through the metal block between its top and bottom surfaces.

A system for providing two parallel light beams spaced-apart a selectable distance, the system including: a first beam splitter configured for reflecting a light beam from a light source to create a first datum light beam, the first beam splitter is fixedly attached to a base; a second beam splitter configured for reflecting a transmitted light beam from the light beam from the light source to create a second datum light beam, a third beam splitter configured for reflecting a transmitted light beam from the light beam from the light source to create a third datum light beam, a fourth beam reflecting device configured for reflecting a transmitted light beam from the light beam from the light source to create a fourth light beam. Each of the second, third beam splitters and fourth beam reflecting device is configured to be slidingly attached to the base.

The head-up display device includes a display element that emits image light and a virtual image optical system. The virtual image optical system includes a lens unit and a free curved surface mirror disposed along the emission direction of the image light in this order from a position close to the display element. The display element is disposed with a tilting attitude with respect to the optical axis of the lens unit with an end on the housing aperture side in an emission surface being close to an incidence surface in the lens unit and with an end on the opposite side of the housing aperture in an emission surface being apart from an incidence surface in the lens unit. The lens unit has an optical characteristic of optically enlarging an optical path length difference according to a virtual image distance difference.

The head-up display device includes a display element that emits image light and a virtual image optical system. The virtual image optical system includes a lens unit and a free curved surface mirror disposed along the emission direction of the image light in this order from a position close to the display element. The display element is disposed with a tilting attitude with respect to the optical axis of the lens unit with an end on the housing aperture side in an emission surface being close to an incidence surface in the lens unit and with an end on the opposite side of the housing aperture in an emission surface being apart from an incidence surface in the lens unit. The lens unit has an optical characteristic of optically enlarging an optical path length difference according to a virtual image distance difference.

A method of additive manufacture is disclosed. The method may include creating, by a 3D printer contained within an enclosure, a part having a weight greater than or equal to 2,000 kilograms. A gas management system may maintain gaseous oxygen within the enclosure atmospheric level. In some embodiments, a wheeled vehicle may transport the part from inside the enclosure, through an airlock, as the airlock operates to buffer between a gaseous environment within the enclosure and a gaseous environment outside the enclosure, and to a location exterior to both the enclosure and the airlock.

An actuator system includes a frame configured to remain stationary relative to a carriage within the frame and connected to the frame by a flexure assembly configured to constrain the carriage for only linear motion along an axis of the actuator system. A rotary base is configured to receive rotational input. Cross-blade flexures operatively connect the carriage to the rotary base, the cross-blade flexures including a plurality of blade flexures and being oriented at an oblique angle to the rotary base and to the axis of the actuator system. A rotary flexure operatively connects the rotary base to the frame. The cross-blade flexures and the rotary flexure are configured to convert rotary motion of the rotary base into linear motion of the carriage and to maintain axial and lateral stiffness.

A magnetic sensor is able to detect a magnetic field applied from a position detecting magnet that makes relative movement as an optical reflector is rotated. Rotation of the optical reflector enables the position detecting magnet to pass through a reference position where a rotation axis, a center or approximate center of the magnetic sensor, and a center or approximate center of the position detecting magnet are located in order on a straight line, as seen in the axial direction of the rotation axis. The magnetic sensor is disposed in an XZ plane that includes a magnetization direction passing through the center or approximate center of the position detecting magnet located at the reference position, and the axial direction of the rotation axis.

A telescope that includes a hollow body, an optical system and mirror positioned in the hollow body,—a device for adjusting tilt and the position of the mirror including a carriage translatably movable in the hollow body, a mirror support plate rigidly connected to the carriage by a hinge, where the carriage is translated by a screw/nut mechanism operated by an adjustment button mounted capable of rotating in a housing portion, the adjustment button is arranged such that rotation of the button causes the carriage to be translatably moved, the adjustment button is associated with a stop member designed to cooperate with a complementary stop member arranged in the housing portion so as to limit button rotation and carriage movement, and at least one actuator movably mounted in the carriage that on the support plate such that moving the actuator changes the tilt of the plate.

A metrology frame configured to receive and secure a workpiece in preparation for an interferometric determination of a spatial profile of the workpiece with the use of one or more retroreflectors removably cooperated with the frame in known pre-determined spatial relationship with respect the fiducial features of not only the workpiece but those of the metrology frame itself The metrology frame is necessarily devoid of a holographic optical element, while the measurement apparatus containing such metrology frame employs a hologram configured to generate at least one alignment optical wavefront that spatially converges on the retroreflector. The hologram is preferably structured as a set of constituent holographic regions (contained in the same, unitary or spatially-complementary housing and/or substrate) that perform different but operationally-complementary functions to facilitate the alignment of the metrology frame with respect to the converging optical wavefront with or without the workpiece in the frame. The optical measurement system employing the metrology frame and the hologram. Methods of optical alignment with use of same.