Electrooptical scanning device

Claim 2

An electrooptical scanning device for deflection of an optical beam of light across an image plane comprising a body of electrooptical material, a source of light for providing a wide beam of light through said body such that the light suffers a single internal reflection from a major surface of said body, a periodic array of spaced electrodes associated with said major surface of said body, at least a portion of the lengths of said electrodes extending in the general direction of travel of said light beam and arranged, in response to a voltage applied thereto, to provide an electric field in said body along said electrode portions to influence the deflection of said light beam at the point of said internal reflection at said major surface, circuit means to individually address each of said electrodes with a selected voltage, the manner of voltage selection to be applied by said circuit means across said electrodes and characterized in that the voltages selected approximte the instantaneous phase retardation desired along the phase front of said light beam, said selection comprising the division of said electrodes into groups serially across said electrode array wherein the voltage values are applied to the electrodes in each electrode group starting from a minimum voltage value at the first electrode of each group and progressing monotonically to a maximum voltage value at the last electrode of each group, the monotonical representation of said voltage progression across each electrode group being an approximation of the instantaneous phase retardation along the phase front of said light beam associated with each electrode group, a change in the instantaneous phase retardation desired along the phase front of said light beam accomplished by changing the number of electrodes in each group in combination with a change in said maximum voltage value and monotonical voltage progression across said electrode groups so that the monotonical representation of said voltage progression across each electrode group approximates a new phase retardation for said light beam representing a new phase front for said light beam.

Claim 3

The scanning device of claim 1 wherein the spatial periodicity of said electrodes is equal.

Claim 4

The scanning device of claim 1 wherein the spatial periodicity of said electrodes is unequal.

Claim 5

The electrooptical scanning device of claim 1 wherein said monotonical representation across each electrode group is linear and at an angle approximating the phase shift angle of the phase front for said light beam exiting said device and being a sawtooth stepwise approximation across said electrode array of the instantaneous phase retardation desired along the phase front of said light beam.

Claim 6

The electrooptical scanning device of claim 1 wherein said monotonical representation across each electrode group is curvalinear and each electrode in each group having a voltage magnitude representative of phase retardation approximating the phase shift angle necessary for focusing said light beam at the positional point of each group electrode at a single spot at an image plane positioned beyond said device and being a sawtooth stepwise approximation across said electrode array of the instantaneous phase retardation desired along the phase front of said light beam to focus said light beam at said image plane spot.

Claim 7

The electrooptical scanning device of claim 1 wherein said electrode array is divided into discrete groups of electrodes, each discrete group to influence the deflection of said light beam at the point of said internal reflection at said major surface independent of the other of said groups, the manner of voltage selection to be applied by said circuit means across the electrodes of each discrete group characterized in that the voltages selected approximate the instantaneous phase retardation desired along the phase front of the portion of said light beam associated with a particular discrete group, said selection comprising the division of said electrodes in each discrete group into subgroups serially across said each discrete group wherein the voltage values are applied to corresponding electrodes in each electrode subgroup starting from a minimum voltage value at the first electrode of each subgroup and progressing monotonically to a maximum voltage value at the last electrode of each subgroup, the monotonical representation of said voltage progression across each electrode subgroup of each of said discrete electrode groups being a stepwise approximation of the instantaneous phase retardation along the phase front of the light beam portion associated with a particular discrete group, a change in the instantaneous phase retardation desired along the phase front of said light beam portions accomplished by changing the number of electrodes in each subgroup in combination with a change in said maximum voltage value and monotonical voltage progression across said electrode subgroups so that the monotonical representation of said voltage progression across each electrode subgroup approximtes a new phase retardation for each of said light beam portions representing a new and different phase front for each of said light beam portions.

Claim 8

The electrooptical scanning device of claim 6 wherein said monotonical representation across each electrode subgroup is linear and at an angle approximating the phase shift angle of the phase front for each of said light beam portions exiting said device and being a sawtooth stepwise approximation across each of said discrete electrode groups of the instantaneous phase retardation along the phase front of each of said light beam portions.

Claim 9

The electrooptical scanning device of claim 6 wherein said monotonical representation across each electrode subgroup is curvalinear and each electrode in each subgroup having a voltage mangitude representative of phase retardation approximating the phase shift angle necessary for focusing said light beam portion at the positional point of each subgroup electrode at a single spot at an image plane positioned beyond said device and being a sawtooth stepwise approximation across each of said discrete electrode groups of the instantaneous phase retardation desired along the phase front of each of said light beam portions to focus each of said light beam portions at a different spot at said image plane.

Claim 10

The electrooptical scanning device of claim 1 wherein said electrodes are disposed on said body major surface.

Claim 11

The electrooptical scanning device of claim 1 wherein said electrodes are disposed on a major surface of a substrate, said substrae major surface being brought into engagement with and pressed against said body major surface.

Claim 12

An electrooptical scanning device for deflection of an optical beam of light across an image plane comprising a body of electrooptical material, a source of light for providing wide beam of light through said body such that the light suffers a single internal reflection from a major surface of said body, a periodic array of spaced electrodes associated with said major surface of said body, at least a portion of the lengths of said electrodes extending in the general direction of travel of said light beam and arranged, in response to a voltage applied thereto, to provide an electric field in said body along said electrode portions to influence the deflection of said light beam at the point of said internal reflection at said major surface, circuit means to individually address each of said electrodes with a selected voltage, the manner of voltage selection to be applied by said circuit means across said electrodes characterized in that the voltages selected approximate the instantaneous phase retardation desired along the phase front of said light beam, said selection comprising the division of said electrodes into groups serially across said electrode array wherein the voltage values are applied to the electrodes in each electrode group starting from a minimum voltage value at the first electrode of each group and progressing monotonically to a maximum voltage value at the last electrode of each group, the slope representation of the progression of said voltages across each electrode group being a sawtooth stepwise approximation of the instantaneous phase retardation along the phase front of said light beam, a change in the instantaneous phase retardation desired along the phase front of said light beam accomplished by changing the number of electrodes in each group in combination with a change in said maximum voltage value and monotonical voltage progression across said electrode groups so that the angle of the slope representation of the voltage progression across each electrode group approximates a new phase shift angle of said light beam representing a new phase front for said light beam.

Claim 13

An electrooptical scanning device for deflection of an optical beam of light across an image plane comprising a body of electrooptical material, a source of light for providing wide beam of light through said body such that the light suffers a single internal reflection from a major surface of said body, a periodic array of spaced electrodes associated with said major surface of said body, at least a portion of the lengths of said electrodes extending in the general direction of travel of said light beam and arranged, in response to a voltage applied thereto, to provide an electric field in said body along said electrode portions to influence the deflection of said light beam at the point of said internal reflection at said major surface, circuit means to individually address each of said electrodes with a selected voltage, the manner of voltage selection to be applied by said circuit means across said electrodes characterized in that the voltages selected approximate the instantaneous phase retardation desired along the phase front of said light beam, said selection comprising the division of said electrodes into groups serially across said electrode array wherein the voltage values are applied to the electrodes in each electrode group starting from a minimum voltage value at the first electrode of each group and progressing monotonically to a maximum voltage value at the last electrode of each group, the slope representation of the progression of said voltages across each electrode group being a sawtooth stepwise approximation of the instantaneous phase retardation along the phase front of said light beam, a change in the instantaneous phase retardation desired along the phase front of said light beam accomplished by changing the number of electrodes in each group in combination with a change in said maximum voltage value and monotonical voltage progression across said electrode groups so that the angle of the slope representation of the voltage progression across each electrode group approximates a new phase shift angle of said light beam representing a new phase front for said light beam.

Claim 14

The electrooptical scanning device of claim 11 wherein the voltage values applied to corresponding electrodes in each electrode group are voltage referenced to an adjacent electrode by an amount, ΔV, with the first electrode of each group starting a minimum voltage value, V o , and the voltages across the electrodes in the group progressing monotonically according to V n =n(n-1)/2, wherein n is the number position of an electrode in each group, to a maximum voltage value, V max =V o +[n(-1)/2]ΔV, at the last electrode of each group.

Claim 15

The electrooptical scanning device of claim 12 wherein wherein the monotonical progression accross an electrode group is V o , V o +ΔV, V o +3ΔV, V o +6ΔV, V o +10ΔV, V o +15ΔV, . . . , V o +[n(n-1)/2]ΔV, the latter value being equivalent to the phase value 2π.

Claim 16

An electrooptical scanning device for deflection of an optical beam of light across an image plane comprising a body of electrooptical material, a source of light for providing a wide beam of light through said body such that the light suffers a single internal reflection from a major surface of said body, a periodic array of spaced electrodes associated with said major surface of said body, at least a portion of the lengths of said electrodes extending in the general direction of travel of said light beam and arranged, in response to a voltage applied thereto, to provide an electric field in said body along said electrode portions to influence the deflection of said light beam at the point of said internal reflection at said major surface. circuit means to individually address each of said electrodes with selected voltages, the manner of voltage selection to be applied by said circuit means across said electrodes characterized in that the voltages selected approximate the instantaneous phase retardation to provide a given intantaneous phase front of said light beam, said selection comprising the division of said electrodes into groups of equal number serially across said electrode array wherein the voltage valves are applied to corresponding electrodes in each electrode group so that each electrode is voltage referenced to an adjacent electrode by an amount, ΔV, starting from a minimum voltage value, V o , at the first electrode of each group and progressing monotonically according to V n =n(n-1)/2, wherein n is the number position of an electrode in each group for the instantaneous phase front, to a maximum voltage value, V max =V o +[n(n-1)/2]ΔV, at the last electrode of each group, the slope representation of the progression of said voltages across each electrode group being a sawtooth stepwise approximation of the instantaneous phase retardation along the phase front of said light beam, a change in the instantaneous phase retardation desired along the phase front of said light beam accomplished by changing the number of electrodes in each group in combination with a change in said maximum voltage value and monotonical voltage progression across said electrode groups so that the angle of the slope representation of said voltage progression across each electrode group approximates a new phase shift angle, Φ, of said light beam representing a new instantaneous phase front for said light beam.

Claim 17

An electrooptical scanning device for deflection of an optical beam of light across an image plane comprising a body of electrooptical material, a source of light for providing a wide beam of light through said body such that the light suffers a single internal reflection from a major surface of said body, a periodic array of spaced electrodes associated with said major surface of said body, at least a portion of the lengths of said electrodes extending in the general direction of travel of said light beam and arranged, in response to a voltage applied thereto, to provide an electric field in said body along said electrode portions to influence the deflection of said light beam at the point of said internal reflection at said major surface. circuit means to individually address each of said electrodes with selected voltages, the manner of voltage selection to be applied by said circuit means across said electrodes characterized in that the voltages selected approximate the instantaneous phase retardation to provide a given intantaneous phase front of said light beam, said selection comprising the division of said electrodes into groups of equal number serially across said electrode array wherein the voltage valves are applied to corresponding electrodes in each electrode group so that each electrode is voltage referenced to an adjacent electrode by an amount, ΔV, starting from a minimum voltage value, V o , at the first electrode of each group and progressing monotonically according to V n =n(n-1)/2, wherein n is the number position of an electrode in each group for the instantaneous phase front, to a maximum voltage value, V max =V o +[n(n-1)/2]ΔV, at the last electrode of each group, the slope representation of the progression of said voltages across each electrode group being a sawtooth stepwise approximation of the instantaneous phase retardation along the phase front of said light beam, a change in the instantaneous phase retardation desired along the phase front of said light beam accomplished by changing the number of electrodes in each group in combination with a change in said maximum voltage value and monotonical voltage progression across said electrode groups so that the angle of the slope representation of said voltage progression across each electrode group approximates a new phase shift angle, Φ, of said light beam representing a new instantaneous phase front for said light beam.

Claim 18

The scanning device of claim 14 wherein the spatial periodicity of said electrodes is equal.

Claim 19

The scanning device of claim 14 wherein the spatial periodicity of said electrodes is unequal.

Claim 20

The electrooptical scanning device of claim 14 wherein the value for V max for an instantaneous phase front is equal to λ o /C o L where λ o is the wavelength of said light beam in free space, C o is an electrooptic constant and L is the length of the electrodes interacting with said light beam at said internal reflection point.

Claim 21

The electrooptical scanning device of claim 14 wherein said electrode array is divided into discrete groups of electrodes, each discrete group to influence the deflection of said light beam at the point of said internal reflection at said major surface independent of the other of said groups, the manner of voltage selection to be applied by said circuit means across the electrodes of each discrete group characterized in that the voltages selected approximate the instantaneous phase retardation desired along the phase front of the portion of said light beam associated with a particular discrete group, said selection comprising the division of said electrodes in each discrete group into subgroups serially across said each discrete group wherein the voltage values are applied to corresponding electrodes in each electrode subgroup starting from a minimum voltage value at the first electrode of each subgroup and progressing monotonically to a maximum voltage value at the last electrode of each subgroup, the monotonical representation of said voltage progression across each electrode subgroup of each of said discrete electrode groups being a stepwise approximation of the instantaneous phase retardation along the phase front of the light beam portion associated with a particular discrete group. a change in the instantaneous phase retardation desired along the phase front of said light beam portions accomplished by changing the number of electrodes in each subgroup in combination with a change in said maximum voltage value and monotonical voltage progression across said electrode subgroups so that the monotonical representation of said voltage progression across said electrode subgroup approximates a new phase retardation for each of said light beam portions representing a new and different phase front for each of said light beam portions.

Claim 22

The electrooptical scanning device of claim 18 wherein said monotonical representation across each electrode subgroup is linear and at an angle approximating the phase shift angle of the phase front for each of said light beam portions exiting said device and being a sawtooth stepwise approximation across each of said discrete electrode groups of the instantaneous phase retardation along the phase front of each of said light beam portions.

Claim 23

The electrooptical scanning device of claim 28 wherein said electrodes are disposed on said body major surface.

Claim 24

The electrooptical scanning device of claim 14 wherein said electrodes are disposed on a major surface of a substrate, said substrate major surface being brought into engagement with and pressed against said body major surface.