초록 ▼

An optical position sensor for indicating the position of a movable body with respect to a reference point. A first optical signal at one wavelength and a second optical signal at a different wavelength, both modulated at a radio frequency, are transmitted through an optical fiber to the reference p

An optical position sensor for indicating the position of a movable body with respect to a reference point. A first optical signal at one wavelength and a second optical signal at a different wavelength, both modulated at a radio frequency, are transmitted through an optical fiber to the reference point at which a semi-reflecting mirror which passes the first signal and reflects the second signal is disposed. The first signal is reflected by the body into the optical fiber, and a phase comparator coupled to the fiber compares the phases of the modulating signals on the reflected first signal and the reflected second signal to determine the position of the body relative to the mirror.

대표청구항 ▼

An optical position sensor for measuring the position of a movable body, said sensor comprising: first and second generators for respectively generating an optical, monochromatic measuring signal of a first wavelength and an optical, monochromatic reference signal of a second wavelength; modulating

An optical position sensor for measuring the position of a movable body, said sensor comprising: first and second generators for respectively generating an optical, monochromatic measuring signal of a first wavelength and an optical, monochromatic reference signal of a second wavelength; modulating means connected to said generators for amplitude modulating the optical signal each of said generators with a radio frequency signal to thereby provide a modulated reference signal and a modulated measuring signal; an optical fiber having first and second ends with said first end coupled to said generators for transmitting within said optical fiber said amplitude modulated reference signal and said amplitude modulated measuring signal to said second end of said optical fiber at a point spaced from said generators; transmitting and reflecting means at said second end of said optical fiber for completely reflecting within said optical fiber said amplitude modulated reference signal and fully transmitting said amplitude modulated measuring signal outside said optical fiber to a body, the position of which is to be measured, and for receiving amplitude measuring signal energy reflected from said body, the amplitude modulating signal on the reflected measuring signal having a phase which is dependent upon the position of said body, and for directing said energy reflected from said body into said optical fiber at said second end; and phase comparing means coupled to said optical fiber at said first end for comparing the phase of the modulating signal on said reference signal with the phase of the modulating signal on said reflected measuring signal for determining the phase difference between the amplitude modulating signal on said reflected measuring signal energy and the amplitude modulating signal on said reference signal, such phase difference indicating the distance of the body from said transmitting and reflecting means.