Patent application number | Description | Published |
20080273244 | Wide field compact imaging catadioptric spectrometer - An imaging catadioptric spectrometer using a Mangin type lens and pupil lens adjacent to a grating. Electromagnetic radiation received by aperture slits is directed to a reflective portion of a Mangin type lens and redirected to a pupil adjacent a diffraction grating. Diffracted light is transmitted through a refractive portion of the Mangin type lens and through a corrector lens to image the spectral components of electromagnetic radiation onto a detector. The detector may be an enhanced detector utilizing an array of smaller spaced detectors. By balancing the powers of the lens elements, a single optical material may be used. In one embodiment, multiple aperture slits are spaced apart and decentered with respect to the optical axis permitting collection of opposing diffraction orders on two detectors. A wide field of view having a low F number is obtained with an operating wavelength range in the infrared from approximately 7.5 to 13.5 microns. The spectrometer is particularly suited to airborne applications. | 11-06-2008 |
20100238440 | Airborne hyperspectral imaging system - A hyperspectral imaging system has fore-optics including primary, secondary and tertiary fore-optics mirrors, and an imaging spectrometer including primary, secondary and tertiary spectrometer mirrors. Light from a distant object is collected by the primary fore-optics mirror, and the tertiary fore-optics mirror forms an intermediate object image at an entrance side of a spectrometer slit. The spectrometer mirrors are configured so that light from an exit side of the slit is diffracted by a grating on the secondary mirror, and an image representing spectral and spatial components of the object is formed by the tertiary spectrometer mirror on a focal plane array. The surface of each mirror of the fore-optics and the spectrometer has an associated axis of symmetry. The mirrors are aligned so that their associated axes coincide to define a common system axis, thus making the imaging system easier to assemble and align in relation to prior systems. | 09-23-2010 |
20120147483 | WIDE FIELD ATHERMALIZED ORTHOSCOPIC LENS SYSTEM - A wide field optically athermalized orthoscopic lens system includes, in order from object to image, a first lens having a negative power, a second lens having a positive power, a third lens group having a positive power, a fourth lens having a positive power and a fifth lens having a negative power. The third lens group includes two lenses having, in order, a first lens with positive power and a second lens with negative power. The powers, shapes, Abbe dispersion values and temperature coefficients of refractive indices of the lenses are selected such that the lens system is athermalized, orthoscopic and achromatized over a wide (e.g. >140° C.) temperature range. | 06-14-2012 |
20140376106 | WIDE FIELD ATHERMALIZED ORTHOSCOPIC LENS SYSTEM - A wide field optically athermalized orthoscopic lens system includes, in order from object to image, a first lens having a negative power, a second lens having a positive power, a third lens group having a positive power, a fourth lens having a positive power and a fifth lens having a negative power. The third lens group includes two lenses having, in order, a first lens with positive power and a second lens with negative power. The powers, shapes, Abbe dispersion values and temperature coefficients of refractive indices of the lenses are selected such that the lens system is athermalized, orthoscopic and achromatized over a wide (e.g. >140° C.) temperature range. | 12-25-2014 |
Patent application number | Description | Published |
20130050839 | ATHERMAL APOCHROMATIC TELECENTRIC F-THETA LENS WITH LOW F-NUMBER - A compact F-theta lens suitable for precise mapping and aerial photography has an F# of not more than 4.5 and a full field of view of 60° (high quality field over) 53°. The lens is near-telecentric to less than 6°, apochromatic from 450 nm to 650 nm, and athermal from −15° C. to +40° C. Embodiments have a focal plane diameter of 104 mm and are compatible for use with a CMOS 1.8 gigapixel multiple FPA. In some embodiments the focal length is 101 mm and the back working distance is more than 10 mm. In embodiments the lens includes three groups of optical elements, with an aperture located between the first and second groups. In some of these embodiments, the first group has at least three elements, while the second and third groups have four and three elements respectively, and the diameter of the first two groups, including housing, is less than 65 mm. | 02-28-2013 |
20130050840 | LOW DISTORTION ATHERMALIZED IMAGING LENS - A compact, lens suitable for airborne photography and mapping has distortion less than 0.6% and is athermal from −15° C. to +40° C. The lens is near-telecentric to less than 11°, apochromatic over the wavelength range 450 nm-650 nm, and has a full field of view of 60° (high quality field over 53°). The lens can be secondary color corrected. In embodiments, the focal length is 101 mm and the back working distance is more than 10 mm. Embodiments have a focal plane diameter of 104 mm and are compatible for use with a CMOS 1.8 gigapixel multiple FPA. In embodiments, the lens comprises three groups of optical elements, with an aperture located within the second optical group. In some embodiments the first group includes two elements, the second group includes six or seven elements, and the third group include three elements. In embodiments the lens (without window) is less than 180 mm long. | 02-28-2013 |