A photogrammetric method and apparatus for the stereoscopic examination and preparation of maps of featured surfaces in which a pair of stereo images is mounted on a carriage and a three dimensional measuring mark can be brought into conjunction with features on the three dimensional optical model produced from the stereo pair. Marking means are provided so that as the measuring mark means and the optical model are moved relatively to one another, drafting can be carried out on one or both of the stereo image pair. The apparatus can also provide for the recording of co-ordinate data of points on the model moved into conjunction with the measuring mark means.
This relates to an image interpretation instrument including a viewing head and a carriage for supporting imagery. A table provides support for a base, such as a map. The head and the carriage are movable from a first position wherein an observer views both the base and the imagery on the carriage and can thus annotate the base with information derived from the imagery, to a second position wherein the observer views only the imagery and can annotate the imagery directly. Attachment devices for the viewing head are described which permit the viewing of a variety of types of imagery.
An apparatus for viewing and measuring using a partially reflective grating superimposed with the object. The invention provides efficient separation of viewing and measurement spectra from a common axis for a clear view of the object in conjunction with an accurate interferometric measuring system.
A photogrammetric stereoplotter using a stereoscopic binocular unit (1) to provide an image of spatially separated masters (4,5) and including a cursor (6) providing X Y coordinates and measuring marks providing Z coordinates in which the X Y Z coordinates are fed through a stereogrammetric unit (7) to a computer (8) with a display and/or printer (12,13) and an interface (14) to a display tube (16) and through an optic train (18) to at least one side of the binocular unit (1), and including a topographic keyboard unit (10) arranged to feed information to record the trace, and optionally a voice recognition unit (20) with two-way communication between operator and computer (8), and means in the computer (8) whereby model coordinates from the said binocular unit (1) are changed to image coordinates by the computer (8) to achieve precise superimposition of the trace image to eliminate visual disturbance.
An electro-optical measuring system in a photogrammetric comparator or stereocompiler comprises a visible light transparent phase grating which is carried upon a surface of the photo support plate of the device. The grating is formed as a composite layer of .lambda./4 films of at least two dielectric materials of different refractive index which are deposited on the support in such a manner as to yield parallel bands in which the two film materials are in alternating sequence from band to band. As a result of this structure which ensures a constant physical and optical thickness with respect to transmitted imaging light over the whole granting pattern, image-degrading diffraction of the transmitted visible light is avoided, yet the grating pattern provides interfering diffraction in reflection which may be utilized in a precise displacement measuring system.
A device for connecting a stereocomparator to an electronic computer to set up an analytic photogrammetric plotter. In the control device of a stereocomparator, some of the stereoscopic exploring motions of the photograms for the plotting take place with a manual control, and an electronic, digital or analog computer receives information and elaborates the same to obtain additional data relating to at least one other motion. Apparatus is provided to translate said additional data into motion.
