Electrooptic information read-out device using polarized laser light

Claim 2

A mechanism for conveying information by means of light obtained from a laser comprising, in combination: a negative temperature medium which is operable when activated to emit coherent light, said light acting when directed back through said medium to effect a lasing action within different filaments of said medium, a partially reflecting mirror at one end of said medium for returning part of the light to said medium and passing the remainder of the light as an output beam, means at the other end of said medium for acting upon selected portions of the emitted light to effect its return through filaments from which it was emitted and maintain lasing action within them, the portions of light returned through said filaments being selected to represent information to be conveyed, and means including a light responsive device arranged in the path of said output beam to provide an indication of the information transmitted, wherein said last-mentioned means includes means arranged between said light responsive device and said partially reflecting mirror for scanning areas on the latter corresponding to laser filaments from which light may be obtained, said scanning means operating when detecting light from any of said filaments to pass such light to said light responsive device.

Claim 3

A mechanism for conveying information by means of light obtained from a laser comprising, in combination: a negative temperature medium which is operable when activated to emit coherent light, said light acting when directed back through said medium to effect a lasing action within different filaments of said medium, a partially reflecting mirror at one end of said medium for returning part of the light to said medium and passing the remainder of the light as an output beam, means at the other end of said medium for acting upon selected portions of the emitted light to effect its return through filaments from which it was emitted and maintain lasing action within them, the portions of light returned through said filaments being selected to represent information to be conveyed, and mEans including a light responsive device arranged in the path of said output beam to provide an indication of the information transmitted, wherein the laser is constructed so as to emit linearly polarized light from any of its filaments in which lasing action takes place, and means arranged between said partially reflecting mirror and said light responsive device for normally blocking the flow of light to the latter but being operable to pass light selectively from different filaments if lasing action is taking place within them, said last-mentioned means including an analyzer which blocks the flow of light from said laser, an electro-optic device arranged between said partially reflecting mirror and said analyzer, and means for directing an electron beam to selected points on said electro-optic device for rotating the polarization of light received at such point from said laser to effect its passage through said analyzer to said light responsive device.

Claim 4

A mechanism for conveying information by means of light obtained from a laser comprising, in combination: a negative temperature medium which is operable when activated to emit coherent light, said light acting when directed back through said medium to effect a lasing action within different filaments of said medium, a partially reflecting mirror at one end of said medium for returning part of the light to said medium and passing the remainder of the light as an output beam, means at the other end of said medium for acting upon selected portions of the emitted light to effect its return through filaments from which it was emitted and maintain lasing action within them, the portions of light returned through said filaments being selected to represent information to be conveyed, and mEans including a light responsive device arranged in the path of said output beam to provide an indication of the information transmitted, wherein the laser is constructed so as to emit linearly polarized light from any of its filaments in which lasing action takes place, and means arranged between said partially reflecting mirror and said light responsive device for normally blocking the flow of light to the latter but being operable to pass light selectively from different filaments if lasing action is taking place within them, said last-mentioned means including an analyzer which blocks the flow of light from said laser, an electro-optic device arranged between said partially reflecting mirror and said analyzer, and means for directing an electron beam to selected points on said electro-optic device for rotating the polarization of light received at such point from said laser to effect its passage through said analyzer to said light responsive device.

Claim 5

A mechanism for conveying information through a light beam from a laser to a point of use comprising, in combination: a magnetic member having different areas magnetized in one direction or another in accordance with binary information, said member arranged in the cavity of said laser so as to reflect light from said areas and effect a polarization of light from laser filaments corresponding to said areas in one direction or another depending on the direction of magnetization, a light responsive device, and means for passing light to said device from different laser filaments selectively when the light therefrom is polarized in a predetermined direction.

Claim 6

A mechanism for conveying information through a light beam from a laser to a point of use comprising, in combination: a magnetic member having different areas magnetized in one direction or another in accordance with binary information, said member arranged in the cavity of said laser so as to reflect light from said areas and effect a polarization of light from laser filaments corresponding to said areas in one direction or another depending on the direction of magnetization, a light responsive device, and means for passing light to said device from different laser filaments selectively when the light therefrom is polarized in a predetermined direction.

Claim 7

The mechanism of claim 3 including means for magnetizing the different areas on said magnetic member in one direction or another selectively.

Claim 8

The mechanism of claim 3 in which said last-mentioned means includes a pair of analyzers which are normally operative to block the passage of light to said light responsive device, and an electro-optic device associated with said analyzers and operable to change the polarization of any portion of the light which may pass one of said analyzers so that it passes the other of said analyzers to said light responsive device.

Claim 9

The mechanism of claim 3 in which said last-mentioned means includes a pair of analyzers arranged in the path of a light beam between said laser and said light responsive device, one of said analyzers being oriented to pass light polarized in one direction and the other being oriented to pass light polarized in a different direction, and an electro-optic device arranged between said analyzers and operable to change the polarization of light passing one of said analyzers from any selected filament so that it also passes the other of said analyzers to said light responsive device.

Claim 10

The mechanism of claim 3 in which said last-mentioned means includes a light deflector arranged between said light responsive device and said laser, said deflector being operable to deflect light of a selected polarity from any laser filament to said light responsive device.

Claim 11

The mechanism of claim 3 in which said last-mentioned means includes a light deflector arranged between said light responsive device and said laser, said deflector including a plurality of birefringent crystals, an electro-optic device arranged at the input side of each of said crystals, said electro-optic devices normally passing light without changing its polarization, and means for applying voltage pulses to said electro-optic devices selectively whereby the polarization of the light passing therethrough is rotated 90*.