A spectrometer 1A includes a package 2 having a stem 4 and a cap 5, an optical unit 10A disposed on the stem 4, and a lead pin 3 for securing the optical unit 10A to the stem 4. The optical unit 10A includes a dispersive part 21 for dispersing and reflecting light entering from a light entrance part 6 of the cap 5, a light detection element 30 having a light detection part 31 for detecting the light dispersed and reflected by the dispersive part 21, a support 40 for supporting the light detection element 30 such that a space is formed between the dispersive part 21 and the light detection element 30, and a projection 11 protruding from the support 40, the lead pin 3 being secured to the projection 11. The optical unit 10A is movable with respect to the stem 4 in a contact part of the optical unit 10A and the stem 4.

A curved diffraction grating includes a substrate and a metal layer. The substrate is a two-dimensional curved plate structure and has a first surface, a second surface and a plurality of microstructures. The first surface is disposed opposite to the second surface, and the microstructures are disposed on the second surface. Each of the microstructures is a saw-tooth structure and has a clear blazed angle. The metal layer is disposed on the microstructures and has a plurality of diffraction structures corresponding to the microstructures. A spectrometer containing the curved diffraction grating and a manufacturing method of the curved diffraction grating are also disclosed.

A spectrometer 1A includes a package 2 having a stem 4 and a cap 5, an optical unit 10A disposed on the stem 4, and a lead pin 3 for securing the optical unit 10A to the stem 4. The optical unit 10A includes a dispersive part 21 for dispersing and reflecting light entering from a light entrance part 6 of the cap 5, a light detection element 30 having a light detection part 31 for detecting the light dispersed and reflected by the dispersive part 21, a support 40 for supporting the light detection element 30 such that a space is formed between the dispersive part 21 and the light detection element 30, and a projection 11 protruding from the support 40, the lead pin 3 being secured to the projection 11. The optical unit 10A is movable with respect to the stem 4 in a contact part of the optical unit 10A and the stem 4.

A spectrometer 1A includes a package 2 having a stem 4 and a cap 5, an optical unit 10A disposed on the stem 4, and a lead pin 3 for securing the optical unit 10A to the stem 4. The optical unit 10A includes a dispersive part 21 for dispersing and reflecting light entering from a light entrance part 6 of the cap 5, a light detection element 30 having a light detection part 31 for detecting the light dispersed and reflected by the dispersive part 21, a support 40 for supporting the light detection element 30 such that a space is formed between the dispersive part 21 and the light detection element 30, and a projection 11 protruding from the support 40, the lead pin 3 being secured to the projection 11. The optical unit 10A is movable with respect to the stem 4 in a contact part of the optical unit 10A and the stem 4.

A Compact and Athermal VNIR/SWIR Spectrometer utilizes a slit, a Mangin lens, a pupil lens adjacent to the diffraction grating, corrector lenses, a beam splitter, field lenses and SWIR and VNIR FPAs. In examples, two corrector lenses are used. Some examples do not utilize field lenses and beam splitter, some examples utilize only the SWIR radiation spectrum. By balancing the powers of the optical elements and Abbe numbers of glasses as well as usage of aspheric surfaces combinations, a monochromatic and polychromatic aberrational correction is achieved; by balancing optical elements refractive indices change with temperature an athermalization is achieved. The overall length of the spectrometer does not exceed 4 inches, and in some examples it is 2.5 inches. A wide field of view and a low F number are obtained with an operating wavelength range from approximately 400 to 2350 nm. The spectrometer is particularly suited to airborne applications.

A spectrometer 1A includes a package 2 having a stem 4 and a cap 5, an optical unit 10A disposed on the stem 4, and a lead pin 3 for securing the optical unit 10A to the stem 4. The optical unit 10A includes a dispersive part 21 for dispersing and reflecting light entering from a light entrance part 6 of the cap 5, a light detection element 30 having a light detection part 31 for detecting the light dispersed and reflected by the dispersive part 21, a support 40 for supporting the light detection element 30 such that a space is formed between the dispersive part 21 and the light detection element 30, and a projection 11 protruding from the support 40, the lead pin 3 being secured to the projection 11. The optical unit 10A is movable with respect to the stem 4 in a contact part of the optical unit 10A and the stem 4.

A spectrometer includes a package having a stem and a cap, an optical unit disposed on the stem, and a lead pin for securing the optical unit to the stem. The optical unit includes a dispersive part for dispersing and reflecting light entering from a light entrance part of the cap, a light detection element having a light detection part for detecting the light dispersed and reflected by the dispersive part, a support for supporting the light detection element such that a space is formed between the dispersive part and the light detection element, and a projection protruding from the support, the lead pin being secured to the projection. The optical unit is movable with respect to the stem in a contact part of the optical unit and the stem.

A Compact and Athermal VNIR/SWIR Spectrometer utilizes a slit, a Mangin lens, a pupil lens adjacent to the diffraction grating, corrector lenses, a beam splitter, field lenses and SWIR and VNIR FPAs. In examples, two corrector lenses are used. Some examples do not utilize field lenses and beam splitter, some examples utilize only the SWIR radiation spectrum. By balancing the powers of the optical elements and Abbe numbers of glasses as well as usage of aspheric surfaces combinations, a monochromatic and polychromatic aberrational correction is achieved; by balancing optical elements refractive indices change with temperature an athermalization is achieved. The overall length of the spectrometer does not exceed 4 inches, and in some examples it is 2.5 inches. A wide field of view and a low F number are obtained with an operating wavelength range from approximately 400 to 2350 nm. The spectrometer is particularly suited to airborne applications.

An optical sensing module, adapted to sense a characteristic of an object by a sensing beam, comprises a carrying substrate, a transparent cover having a reflective surface thereon, a side wall, an optical grating, and an optical sensor. The reflective surface has a light-transmissive opening that exposes a part of the transparent cover. The side wall is disposed around the carrying substrate and is located between the carrying substrate and the transparent cover. The optical grating is disposed on the carrying substrate and a position of the optical grating corresponds to the light-transmissive opening. The optical sensor is disposed on the carrying substrate and is located at a side of the optical grating, wherein the carrying substrate, the side wall and the transparent cover form a vacuum chamber. The optical grating and the optical sensor are disposed in the vacuum chamber.

A spectrometer includes a package having a stem and a cap, an optical unit disposed on the stem, and a lead pin for securing the optical unit to the stem. The optical unit includes a dispersive part for dispersing and reflecting light entering from a light entrance part of the cap, a light detection element having a light detection part for detecting the light dispersed and reflected by the dispersive part, a support for supporting the light detection element such that a space is formed between the dispersive part and the light detection element, and a projection protruding from the support, the lead pin being secured to the projection. The optical unit is movable with respect to the stem in a contact part of the optical unit and the stem.