초록 ▼

An adaptive slant range compensator, suitable for use with an optical mapping system for remote viewing, comprises a logarithmic amplifier which compresses an analog input signal having a wide range of values to a tractable range. An analog-to-digital (A/D) converter converts the compressed signal t

An adaptive slant range compensator, suitable for use with an optical mapping system for remote viewing, comprises a logarithmic amplifier which compresses an analog input signal having a wide range of values to a tractable range. An analog-to-digital (A/D) converter converts the compressed signal to a 10-bit binary number. The digitized compressed data is then used to address antilog programmable read-only memories (PROMs) which contain the antilog of the address data in scientific notation. Control and data processing circuits are used to accumulate sample scans from the antilog PROMs in a summing memory, calculate an average scan from the accumulated sample scans, and transfer this average to a working memory. The data stored in the working memory is used to drive an attenuation/amplification network that divides succeeding scans by the stored average scan. In this way, the inverse transfer function is applied to the analog input signal, which forms another input to the attenuation/amplification network.

대표청구항 ▼

An optical system, to be used with a light source, for mapping objects located in an underwater environment, comprising: a first optical means, adapted to receive light from the light source, for transmitting the light produced by the light source to the object area to be mapped, thereby illuminatin

An optical system, to be used with a light source, for mapping objects located in an underwater environment, comprising: a first optical means, adapted to receive light from the light source, for transmitting the light produced by the light source to the object area to be mapped, thereby illuminating the area; and a second optical means comprising: an input means, adapted to receive reflected light from the illuminated object area, or plane; an output means for conformally transforming, that is, conformally mapping, images of all objects in the object plane to an image plane located externally of the second optical means: and means, disposed between the second optical means and the image plane, for masking light propagating between the optical means and the image plane, the masking means having a circular configuration; and means adapted to receive illumination from the transforming means, for compensating for the absorption losses of the light as a function of the range to various parts of the object area.