Device and method for determining displacement

Claim 1

Apparatus for monitoring a variable parameter, comprising a color detecting means, a light source adapted to propagate polychromatic light along a path to said color detecting means; means for monitoring and translating a change in said variable parameter into a change in the color of the polychromatic light incident on said color detecting means, the color detecting means comprising at least two discrete color detectors which have respective response characteristics such that the output signals X, Y . . . of the detectors correspond respectively to X=P (λ) x (λ) dλ, Y=P (λ) y (λ) dλ. . . , where P(λ) is the spectral power distribution at wavelength λ and x (λ), y (λ) . . . are color matching functions corresponding to the respective response characteristics of the detectors and means for analogue manipulation of X, Y . . . to enable the values of x and y in the Chromaticity Diagram corresponding to the incident color to be calculated, thereby enabling quantification of the change in color at the color detecting means and hence quantification of the change in said variable parameter.

Claim 5

A method of monitoring a variable parameter, comprising the steps of providing a polychromatic light signal; translating a change in the parameter into a change in color of the polychromatic light signal; and identifying the color of the polychromatic light signal with a color detection system comprising at least two discrete color detectors which have respective response characteristics such that the output signals X, Y . . . of the detectors correspond respectively to X=Pλxλdλ, Y=Pλyλdλ, where Pλ is the spectral power distribution at wavelength λ and xλ, yλ. . . are color matching functions corresponding to the respective response characteristics of the detectors, and means for analogue manipulation of X, Y . . . to enable the values of x and y in the Chromaticity Diagram corresponding to the incident color to be calculated, the new color being indicative of the new value of said parameter whereby the change in the parameter can then be quantified.

Claim 6

A method of monitoring a variable parameter, comprising the steps of providing a polychromatic light signal; translating a change in the parameter into a change in color of the polychromatic light signal; and identifying the color of the polychromatic light signal with a color detection system comprising at least two discrete color detectors which have respective response characteristics such that the output signals X, Y . . . of the detectors correspond respectively to X=Pλxλdλ, Y=Pλyλdλ, where Pλ is the spectral power distribution at wavelength λ and xλ, yλ. . . are color matching functions corresponding to the respective response characteristics of the detectors, and means for analogue manipulation of X, Y . . . to enable the values of x and y in the Chromaticity Diagram corresponding to the incident color to be calculated, the new color being indicative of the new value of said parameter whereby the change in the parameter can then be quantified.

Claim 7

An apparatus for monitoring a variable parameter, comprising: (a) a color detecting means which detects the colors of incident radiation; (b) the color detector means comprising at least two discrete color detectors which have respective response characteristics such that the output signals X, Y . . . of the detectors correspond respectively X=P (λ) x (λ) dλ, Y=P (λ) y (λ) dλ. . . where P(λ) is the spectral power distribution at wavelength λ and x (λ), y (λ) . . . are color matching functions corresponding to the respective response characteristics of the detectors, and means for analogue manipulation of X, Y . . . to enable the values of x and y in the Chromaticity Diagram corresponding to the incident color to be calculated; (c) a light source which propagates a polychromatic light beam along a path to said color detecting means; (d) a radiation modulation means mechanically associated with said parameter to be monitored so that variation of said parameter causes adjustment of the radiation modulating means in said path such as to vary the color of the light reaching the color detecting means; (e) the radiation modulation means comprising a filter which attenuates the intensity of transmitted wavelengths to different degrees dependent upon its position in relation to said path of the polychromatic light signal, whereby the color transmitted by the radiation modulation means to the color detecting means varies with the adjustment thereof and hence with variation of said parameter.

Claim 8

An apparatus for monitoring a variable parameter, comprising: (a) a color detecting means which detects the colors of incident radiation; (b) the color detector means comprising at least two discrete color detectors which have respective response characteristics such that the output signals X, Y . . . of the detectors correspond respectively X=P (λ) x (λ) dλ, Y=P (λ) y (λ) dλ. . . where P(λ) is the spectral power distribution at wavelength λ and x (λ), y (λ) . . . are color matching functions corresponding to the respective response characteristics of the detectors, and means for analogue manipulation of X, Y . . . to enable the values of x and y in the Chromaticity Diagram corresponding to the incident color to be calculated; (c) a light source which propagates a polychromatic light beam along a path to said color detecting means; (d) a radiation modulation means mechanically associated with said parameter to be monitored so that variation of said parameter causes adjustment of the radiation modulating means in said path such as to vary the color of the light reaching the color detecting means; (e) the radiation modulation means comprising a filter which attenuates the intensity of transmitted wavelengths to different degrees dependent upon its position in relation to said path of the polychromatic light signal, whereby the color transmitted by the radiation modulation means to the color detecting means varies with the adjustment thereof and hence with variation of said parameter.