Photoelectric transducer

Claim 2

An electro-optical device comprising an electrically conductive and optically reflective membrane; a source of radiation; a pair of detectors; a lens system for focussing the radiation and for imaging the focussed radiation onto said pair of detectors, said pair of detectors being displaced with reference to one another on either side of the image plane of the focussed radiation; a beam splitter for splitting the imaged radiation reflected by said membrane onto said pair of detectors, so that movement of the membrane creates output signals from said detectors which differ in phase; electrical means for deriving from the outputs of the pair of detectors an electrical signal the sign of which is dependent on the direction of displacement of said membrane and the magnitude of which is dependent on the amount of displacement; and at least one electrostatic electrode mounted adjacent to said membrane for driving the membrane toward its null position in response to a negative feedback signal proportional to said electrical signal.

Claim 3

An electro-optical device comprising an electrically conductive and optically reflective membrane; a source of radiation; at least one detector; a lens system for focussing the radiation and for imaging the focussed radiation onto said at least one detector; electrical means for deriving from the at least one detector output an electrical signal the sign of which is dependent on the direction of displacement of said membrane and the magnitude of which is dependent on the amount of displacement; at least one electro-static electrode mounted adjacent to said membrane for driving the membrane toward its null position in response to a negative feedback signal proportional to said electrical signal derived from said detector output, and wherein the electro-optical device is utilized as a voltage comparator and including an additional electrostatic electrode mounted adjacent said membrane on its side opposite said one electrostatic electrode with an unknown voltage to be measured applied to said second electrostatic electrode to produce displacement of said membrane.

Claim 4

An electro-optical device comprising an electrically conductive and optically reflective membrane; a source of radiation; at least one detector; a lens system for focussing the radiation and for imaging the focussed radiation onto said at least one detector; electrical means for deriving from the at least one detector output an electrical signal the sign of which is dependent on the direction of displacement of said membrane and the magnitude of which is dependent on the amount of displacement; at least one electro-static electrode mounted adjacent to said membrane for driving the membrane toward its null position in response to a negative feedback signal proportional to said electrical signal derived from said detector output, and wherein the electro-optical device is utilized as a voltage comparator and including an additional electrostatic electrode mounted adjacent said membrane on its side opposite said one electrostatic electrode with an unknown voltage to be measured applied to said second electrostatic electrode to produce displacement of said membrane.

Claim 5

An electro-optical device comprising an electrically conductive and optically reflective membrane; a source of radiation; a lens system for focussing the radiation onto said membrane; means for impressing on said membrane a sinusoidal wave form at a pre-determined frequency for a displacement of approximately one quarter of a wave length of the raidation from said source; phase sensitive means for deriving from said detector a signal, the amplitude and sign of which are dependent on the direction and amplitude of movement respectively of the membrane under an additional force; and at least one electrostatic electrode mounted adjacent to said membrane for drivIng said membrane towards its null position in response to a negative feed-back signal proportional to the output signal derived by said phase sensitive means.

Claim 6

An electro-optical device comprising an electrically conductive and optically reflective membrane; a source of radiation; a lens system for focussing the radiation onto said membrane; means for impressing on said membrane a sinusoidal wave form at a pre-determined frequency for a displacement of approximately one quarter of a wave length of the raidation from said source; phase sensitive means for deriving from said detector a signal, the amplitude and sign of which are dependent on the direction and amplitude of movement respectively of the membrane under an additional force; and at least one electrostatic electrode mounted adjacent to said membrane for drivIng said membrane towards its null position in response to a negative feed-back signal proportional to the output signal derived by said phase sensitive means.

Claim 7

A device as claimed in claim 3 wherein said detector has a bias voltage for its operation, and wherein said phase sensitive means comprises means for varying the bias to said detector with a sinusoidal wave form of the same frequency and phase as the wave form impressing oscillations on said membrane.

Claim 8

An electro-optical device in accordance with claim 3 and utilized as a microphone for acoustic energy and wherein one side of said electrically conductive and optically reflective membrane is exposed to the acoustic energy and displaced thereby.

Claim 9

An electro-optical device in accordance with claim 3 and utilized as a manometer for measuring pressure, and wherein one side of said electrically conductive and optically reflective membrane is exposed to the pressure being measured to cause a displacement thereof.

Claim 10

An electro-optical device in accordance with claim 3 and utilized as a voltage comparator and including an additional electrostatic electrode mounted adjacent said membrane on its side opposite said one electrostatic electrode with an unknown voltage to be measured applied to said second electrostatic electrode to produce displacement of said membrane.

Claim 11

An electro-optical device comprising an electrically conductive and optically reflective membrane; a source of radiation; an interferometric system, including first and second detectors and a reference mirror for focussing radiation from said source along one path onto said membrane and from said membrane onto said first detectors so as to provide a first path length, and for focussing radiation from said source along a second path to said reference mirror and from said reference mirror onto said second detector so as to provide a second path length whereby displacement of said membrane from its null position causes said detectors to provide output signals which differ in phase; and an electrostatic means for driving the membrane towards its null position in response to a negative feed-back signal derived from said detector output signals.

Claim 12

An electro-optical device comprising an electrically conductive and optically reflective membrane; a source of radiation; an interferometric system, including first and second detectors and a reference mirror for focussing radiation from said source along one path onto said membrane and from said membrane onto said first detectors so as to provide a first path length, and for focussing radiation from said source along a second path to said reference mirror and from said reference mirror onto said second detector so as to provide a second path length whereby displacement of said membrane from its null position causes said detectors to provide output signals which differ in phase; and an electrostatic means for driving the membrane towards its null position in response to a negative feed-back signal derived from said detector output signals.

Claim 13

A device as claimed in claim 8 and comprising phase sensitive means for deriving from the detector output signals an electrical signal the sign of which is dependent on the direction of displacement of the membrane, and the magnitude of which is dependent upon the amount of displacement of said membrane, and means for applying said electrical signal to said electrostatic means to oppose the force displacing said membrane.

Claim 14

An electro-optical device in accordance with claim 8 and utilized as a microphone for acoustic energy and wherein one side of said electrically conductive and optically reflective membrane is exposed to the acoustic energy and displaced thereby.

Claim 15

An electro-optical device in accordance with claim 8 and utilized as a manometer for measuring pressure, and wherein one side of said electrically conductive and optically reflective membrane is exposed to the pressure being measured to cause a displacement thereof.

Claim 16

An electro-optical device in accordance with claim 8 and utilized as a voltage comparator and including an additional electrostatic electrode disposed on one side of said membrane opposite said electrostatic means, with the unknown voltage to be measured applied to said additional electrostatic electrode for displacing said membrane.

Claim 17

An electro-optical device comprising an electrically conductive and partially optically reflective membrane, a source of radiation mounted on one side of said membrane; a detector mounted equidistant on the other side of said membrane; a lens system on either side of said membrane, each lens system having a centrally fully reflective region; the lens system providing optically conjugate paths on either side of said membrane so that displacement of the membrane causes a variation in the output of said detector; and an elecTrostatic means for driving the said membrane towards its null position in response to a negative feed-back signal derived from said detector output signal.

Claim 18

An electro-optical device comprising an electrically conductive and partially optically reflective membrane, a source of radiation mounted on one side of said membrane; a detector mounted equidistant on the other side of said membrane; a lens system on either side of said membrane, each lens system having a centrally fully reflective region; the lens system providing optically conjugate paths on either side of said membrane so that displacement of the membrane causes a variation in the output of said detector; and an elecTrostatic means for driving the said membrane towards its null position in response to a negative feed-back signal derived from said detector output signal.

Claim 19

An electro-optical device in accordance with claim 13 and utilized as a manometer for measuring pressure, and wherein one side of said electrically conductive and optically reflective membrane is exposed to the pressure being measured to cause a displacement thereof.

Claim 20

An electro-optical device in accordance with claim 13 and utilized as a manometer for measuring pressure, and wherein one side of said electrically conductive and optically reflective membrane is exposed to the pressure being measured to cause a displacement thereof.

Claim 21

An electro-optical device in accordance with claim 13 and utilized as a voltage comparator and including an additional electrostatic means disposed on a side of said membrane opposite said electrostatic means, with an unknown voltage applied to said additional electrostatic means.

Claim 22

A device as claimed in claim 13 and including means for oscillating said membrane at a predetermined frequency for a displacement of approximately a quarter of the wave length of the radiation from said source.

Claim 23

A device as claimed in claim 17 and including a filter for removing from the detector output signal the modulation imparted by said oscillation at the pre-determined frequency so that the resultant signal has, after processing in said phase sensitive means, a magnitude and sign dependent on any additional force causing displacement of said membrane.

Claim 24

A device as claimed in claim 18 and including means for applying said resultant signal to said electrostatic means so as to oppose the force causing the displacement of said membrane.

Claim 25

A device as claimed in claim 19 wherein the electrostatic means comprises a pair of electrodes mounted one on either side of said membrane.