Ballistic linear bidirectional scanner system

Claim 2

A linear scanning system operative to bidirectionally scan radiation incident on said system over a field of view and comprising: means for redirecting radiation received from said field of view; means for supporting said redirecting means for ballistic rotation about an axis through a rotational angle and providing a low frictional restraint to rotation of said redirecting means, whereby the ballistic rotation rate of said redirecting means is generally maintained through said rotation angle; a rotation cycle being defined as two complete traversals through said rotation angle in opposed directions by said redirecting means; an electromagnetic transducer including plunger means disposed at at least one angular limit of said rotation angle to contact said redirecting means at said at least one limit and operative to reverse the rotation of said redirecting means by applying a torque impulse to said redirecting means during contact therewith over a time interval which is a small fraction of the rotation cycle of said redirecting means, thereby to provide ballistic scanning by said redirecting means over substantially all of said rotation cycle; first and second electrical contacts mounted on a reverse surface of said redirecting means and positioned along a line orthogonal to said axis; said plunger means comprising: first and second electrical coils having the respective axes thereof generally directed toward said first and second electrical contacts; first and second plungers slidably mounted within said first and second electrical coils respectively; said plungers being responsive to the application of electrical excitation to said coils to cause said plungers to be impelled toward said first and second contacts; third and fourth contacts respectively secured to said first and second plungers on ends which respectively confront said first and second contacts, whereby said third and fourth contacts are operative to alternately contact said first and second contacts during oscillation of said redirecting means; said electromagnetic transducer including: first means for applying electrical excitation to said first coil in response to electrical contact between said first and third contacts thereby to cause rotation of said redirecting means away from said first coil toward said second coil; and second means for applying electrical excitation to said second coil in response to electrical contact between said second and fourth contacts thereby to cause rotation of said redirecting means away from said second coil toward said first coil.

Claim 3

The linear scanning system of claim 1 further including means for retaining said first and second plungers in a retracted position within said first and second coils in the absence of electrical excitation to said coils.

Claim 4

The linear scanning system according to claim 1 further including first and second resilient pads secured respectively between said third contact and the end of said first plunger and between said fourth contact and the end of said second plunger, said first and second pads providing a mechanical aid in the reversal of the rotation of said redirecting means.

Claim 5

The linear scanning system according to claim 1 wherein said first and second means for applying electrical excitation to said first and second coils include: first and second capacitors; and means for charging said first and second capacitors; said first capacitor being serially connected with said first coil, said first contact and said third contact to cause discharge of said first capacitor through said first coil when said first and third contacts touch; said second capacitor being serially connected with said second coil, said second contact and said fourth contact to cause discharge of said second capacitor through said second coil when said second and fourth contacts touch.

Claim 6

A linear scanning system operative to bidirectionally scan radiation incident on said system over a field of view and comprising: means for redirecting radiation received from said field of view; means for supporting said redirecting means for ballistic rotation about an axis through a rotational angle and providing a low frictional restraint to rotation of said redirecting means, whereby the ballistic rotation rate of said redirecting means is generally maintained through said rotation angle; a rotation cycle being defined as two complete traversals through said rotation angle in opposed directions by said redirecting means; an electromagnetic transducer including plunger means disposed at at least one angular limit of said rotation angle to contact said redirecting means at said at least one limit and operative to reverse the rotation of said redirecting means by applying a torque impulse to said redirecting means during contact therewith over a time interval which is a small fraction of the rotation cycle of said redirecting means, thereby to provide ballistic scanning by said redirecting means over substantially all of said rotaTion cycle; said electromagnetic transducer including: means for moving said plunger means in response to a signal; stabilizing means for producing a torque impulse which increases in magnitude with the interval between torque impulses; a capacitor; means for electrically charging said capacitor with time; and means for discharging said capacitor to supply said current to said means for moving said plunger means in response to said redirecting means being sensed at said at least one angular limit in the rotation thereof.

Claim 7

A linear scanning system operative to bidirectionally scan radiation incident on said system over a field of view and comprising: means for redirecting radiation received from said field of view; means for supporting said redirecting means for ballistic rotation about an axis through a rotational angle and providing a low frictional restraint to rotation of said redirecting means, whereby the ballistic rotation rate of said redirecting means is generally maintained through said rotation angle; a rotation cycle being defined as two complete traversals through said rotation angle in opposed directions by said redirecting means; an electromagnetic transducer including plunger means disposed at at least one angular limit of said rotation angle to contact said redirecting means at said at least one limit and operative to reverse the rotation of said redirecting means by applying a torque impulse to said redirecting means during contact therewith over a time interval which is a small fraction of the rotation cycle of said redirecting means, thereby to provide ballistic scanning by said redirecting means over substantially all of said rotaTion cycle; said electromagnetic transducer including: means for moving said plunger means in response to a signal; stabilizing means for producing a torque impulse which increases in magnitude with the interval between torque impulses; a capacitor; means for electrically charging said capacitor with time; and means for discharging said capacitor to supply said current to said means for moving said plunger means in response to said redirecting means being sensed at said at least one angular limit in the rotation thereof.

Claim 8

The linear scanning system of claim 5 wherein said means for electrically charging said capacitor provides a charge linearly increasing with time.

Claim 9

A linear scanning system operative to bidirectionally scan incident radiation over a field of view, and comprising: a frame; a mirror having a reflecting surface; low frictional restraint bearings for rotationally supporting said mirror in said frame for ballistic rotation of said mirror through a rotation angle about an axis generally parallel to the reflecting surface of said mirror and whereby the ballistic rotation rate of said mirror is generally maintained through said rotation angle; a rotation cycle being defined as two complete traversals through said rotation angle in opposed directions by said mirror; first and second electrical contacts mounted to said mirror; third and fourth electrical contacts respectively secured to alternately contact said first and second contacts during oscillation of said mirror; first and second electrically actuable plunger mechanisms, disposed at first and second angular limits of said rotation angle and operative to provide torque impulses to said mirror at said first and second limits; said torque impulses being applied to said mirror over a time interval which is a small fraction of the rotation cycle of said mirror, thereby to provide ballistic scanning by said mirror over substantially all of said rotation cycle; said plunger mechanisms including: first and second electrical coils mounted to said frame, the respective axes thereof intercepting said mirror at points a set distance from said axis; first and second plunger members slidably mounted within said first and second electrical coils respectively; first and second high resiliency cushions secured respectively to said first plunger member and said second plunger member on ends which respectively confront said mirror at said points a set distance from said axis, said cushions being operative to aid in reversing rotation of said mirror; and said first and second plunger members being responsive to the application of electrical excitation to said coils to be impelled toward said mirror; and first and second electrical circuits, operative to apply electrical excitation to said first and second coils, said circuits including: first and second capacitors; means for charging said first and second capacitors; means for interconnecting said first capacitor with said first coil and said first and third contacts to discharge said first capacitor through said first coil in response to touching of said first and third contacts; and means for interconnecting said second capacitor with said second coil and said second and fourth contacts to discharge said second capacitor through said second coil in response to touching of said second and fourth contacts.

Claim 10

A linear scanning system operative to bidirectionally scan incident radiation over a field of view, and comprising: a frame; a mirror having a reflecting surface; low frictional restraint bearings for rotationally supporting said mirror in said frame for ballistic rotation of said mirror through a rotation angle about an axis generally parallel to the reflecting surface of said mirror and whereby the ballistic rotation rate of said mirror is generally maintained through said rotation angle; a rotation cycle being defined as two complete traversals through said rotation angle in opposed directions by said mirror; first and second electrical contacts mounted to said mirror; third and fourth electrical contacts respectively secured to alternately contact said first and second contacts during oscillation of said mirror; first and second electrically actuable plunger mechanisms, disposed at first and second angular limits of said rotation angle and operative to provide torque impulses to said mirror at said first and second limits; said torque impulses being applied to said mirror over a time interval which is a small fraction of the rotation cycle of said mirror, thereby to provide ballistic scanning by said mirror over substantially all of said rotation cycle; said plunger mechanisms including: first and second electrical coils mounted to said frame, the respective axes thereof intercepting said mirror at points a set distance from said axis; first and second plunger members slidably mounted within said first and second electrical coils respectively; first and second high resiliency cushions secured respectively to said first plunger member and said second plunger member on ends which respectively confront said mirror at said points a set distance from said axis, said cushions being operative to aid in reversing rotation of said mirror; and said first and second plunger members being responsive to the application of electrical excitation to said coils to be impelled toward said mirror; and first and second electrical circuits, operative to apply electrical excitation to said first and second coils, said circuits including: first and second capacitors; means for charging said first and second capacitors; means for interconnecting said first capacitor with said first coil and said first and third contacts to discharge said first capacitor through said first coil in response to touching of said first and third contacts; and means for interconnecting said second capacitor with said second coil and said second and fourth contacts to discharge said second capacitor through said second coil in response to touching of said second and fourth contacts.