Systems and methods for determining the position of a device or vehicle by using celestial information captured by an imaging apparatus. The systems and methods identify a star set in the celestial information, generate a star set fingerprint and compare the star set fingerprint with reference celestial information. Once a comparison is made, the location of the device or vehicle can be determined and used within a celestial navigation system.

The present invention relates to a method for readjusting a parallactic or azimuthal mounting, comprising a device which is intended for positioning and moving a telescope with a camera and can be aligned and readjusted by means of at least one image sensor and an electromotorized controller, characterized in that the image sensor acts as a main recording sensor of the camera and at the same time as an alignment sensor and readjustment control sensor, wherein before and after a main image is taken at least one control image is taken with a shorter exposure time and these control images are compared with one another, or at least a main image itself acts as a control image and is compared with at least one previous main image, or a short-exposed control image is compared with the main image itself and the correction values for the readjustment of the mounting are determined by the image offset and the time difference of the images taken. The method is the prerequisite for easy, error-free operation of an astronomical mounting for the purpose of long-exposure astronomical photography.

Multiple mode star tracker methods and systems in which attitude information and image information is generated are provided. The multiple mode star tracker includes a detector having a plurality of pixels arranged in a focal plane array. The detector is operated to obtain multiple image frames from within a field of view containing a plurality of stars. For each of the image frames, the attitude of the detector and in turn the attitude of each pixel is determined. Based on the attitude quaternion of the individual pixels within a plurality of frames, image data from the plurality of frames is co-added or stacked to form a composite image. The co-addition of multiple frames of image data enables or facilitates the detection of dim objects by the multiple mode star tracker. Moreover, embodiments of the present disclosure enable the attitude quaternion for individual pixels within individual frames to be determined using the multiple mode star tracker function of the instrument, and without requiring attitude information provided by a separate device, such as a gyroscope.

A star tracker includes a lens slice, a pixelated image sensor, an ephemeral database and a processor configured to estimate attitude, orientation and/or location of the star tracker based on an image of one or more celestial objects projected by the lens slice onto the pixelated image sensor. The lens slice is smaller and lighter than an optically comparable conventional lens, thereby making the star tracker less voluminous and less massive than conventional star trackers. A lens slice is elongated along one axis. Optical performance along the elongation axis is comparable to that of a conventional circular lens of equal diameter. Although optical performance along a width axis, perpendicular to the elongation axis, of a lens slice can be significantly worse than that of a conventional lens, use of two orthogonal lens slices provides adequate optical performance in both axes, and still saves volume and mass over a conventional lens.

A multi-beam optical phased array on a single planar waveguide layer or a small number of planar waveguide layers enables building an optical sensor that performs much like a significantly larger telescope. Imaging systems use planar waveguides created using micro-lithographic techniques. These imagers are variants of phased arrays, common and familiar from microwave radar applications. However, there are significant differences when these same concepts are applied to visible and infrared light.

A method is provided. The method comprises: receiving incident light, from an object surface, on a top surface of a holographic optical field flattener (HOFF); transforming direction of light, with a hologram, if the light is incident on a portion of the HOFF at an angle equal to a non-zero field angle of the portion; and emitting transformed light from a bottom surface of the HOFF.

A zero-optical-path-length-difference optical phased array built with essentially planar photonic devices determines a direction to an incoherent optical source, such as a star. The phased array can replace a 3-dimensional star tracker with a nearly 2-dimensional system that is smaller and lighter. The zero-optical-path-length-difference phased array can be optically connected to an interferometer. Driven by a light source, the zero-optical-path-length-difference phased array can be used as an optical projector.

System and method for determining a position of a target in an unbiased 3D measurement space: generating 2D measurement data in focal planes of each sensor; calculating a line of sight (LOS) from the target for each sensor; intersecting the LOSs and finding the closest intersection point in a 3D space; calculating a boresight LOS in 3D for each sensor; intersecting the boresight lines of sights for each sensor, and finding the closest intersection point in the 3D space to define an origin for forming the unbiased 3D measurement space; and forming local unbiased 3D estimates of the position of the target in the unbiased 3D measurement space as a difference between a closest point of the target LOS and a closest point of the boresight LOS.

The invention concerns a device (1) for locating a target, comprising: a camera (2) that can be oriented in an orientation in view of the target so that the camera acquires an image of the target, and an orientation in view of a star so that the camera acquires at least one image of the star, an inertial unit (4) configured to calculate position and orientation data of the camera (2), a resetting module (6) configured to a apply stellar resetting to the data on the basis of the image of the star, in order to produce reset data, a location module (8) configured to estimate a position of the target (T) from the image of the target (T) and the reset data, a communication interface for communicating with an operator station, the camera (2) passing from one orientation to the other in response to the reception, by the interface, of a command sent by the operator station.

An Off Axis Guider specifically designed with internal mechanically controlled placement of one or more prisms which allow the user to select stars in the telescope's field of view without obscuring the primary cameras' image capturing ability.