公开(公告)号：DE1547383A1

公开(公告)日：1970-01-22

申请号：DE1547383

申请日：1966-12-24

Applicant: IBM

Inventor： JEROME HARRIS THOMAS

IPC: A47G27/02 ,  G02F1/31 ,  H01S3/101 ,  G02F1/26

Abstract: 1,111,058. Lasers. INTERNATIONAL BUSINESS MACHINES CORPORATION. 2 Nov., 1966 [29 Dec., 1965], No. 49049/66. Heading H1C. [Also in Division G2] An optical scanner providing a circular scan comprises a source 10 of linearly polarized light, Fig. 1, a polarization rotator 26, and an analyser 50 receiving the rotator output and passing only that filament 58 of the polarized light beam which is polarized in a given direction, the rotator being electrically controlled so as to produce a variable polarization rotation and thus enable different light filaments to become effective in turn along the scanning path. In the arrangement shown the linear polarization 62 of each light filament emitted by a laser light source is tangential to a circumference about the geometric axis, and the rotator comprises a quarter wave plate 28 and two vertically-spaced and independently energized electro-optic crystals 30, 32 with transparent electrodes 34, 36, 42, 44. The use of two electro-optic crystals is necessary to enable the analyser 50 to differentiate between diametrically-opposed light filaments which have parallel linear polarizations. The light source, Fig. 2, comprises a frusto-conical bi-refringent crystal having its optic axis 16 parallel to the geometric axis 18, the centre of the crystal being formed with two conical cavities 20, 24. This crystal totally reflects linearly polarized ordinary rays 58 of incident light 54 and disperses the extraordinary rays 56. The reflecting laser crystal and a partially transmitting mirror 52 together form the laser resonator. In an alternative arrangement, Fig. 4, a laser comprises a right circular cylindrical crystal rod 80 having its optic axis 84 inclined at 60 degrees to the geometric axis 82, the resonator being formed by separate mirrors 86, 88. As all the light emitted by the crystal is linearly polarized in the same direction, selection of a required light filament after rotation by a rotator 90 comprising an electro-optic crystal 92 and a quarter wave plate 102 is effected by an analyser formed of several analyser segments 106-118 radially oriented with respect to the geometric axis. The crystal 92 may be divided. In a modification laser action is not used, the crystal of Fig. 1, being illuminated from a narrow-band light source 72, Fig. 3, through a collimating lens 74 and a beam splitter 76. End illumination of the crystal 80 is used in the modified Fig. 4 arrangement, Fig. 5 (not shown). In both cases the resonator components are omitted.

公开(公告)号：DE1564209A1

公开(公告)日：1972-01-20

申请号：DE1564209

申请日：1966-12-09

Applicant: IBM DEUTSCHLAND

Inventor： JEROME HARRIS THOMAS ,  MAX ERHARD

IPC: H01S3/05 ,  H01S3/107 ,  H01S3/08

Abstract: 1,100,506. Lasers. INTERNATIONAL BUSINESS MACHINES CORPORATION. 2 Nov., 1966 [16 Dec., 1965], No. 49048/66. Heading H1C. In order to select a particular frequency or frequencies of operation in a laser, a frequency selector including an electrooptical crystal is inserted in the laser cavity. In the embodiment of Fig. 2 a helium-neon laser tube 21 with Brewster angle windows is inserted in cavity 25, 26 together with the frequency selector 27. The latter cavity comprises a quartz crystal 28, an electro-optical crystal 29 controlled by a variable D.C. voltage 31, and a quarter-wave plate 30 and is enclosed by Brewster angle windows 34, 35 and filled with an index matching fluid. Because the Brewster angle windows linearly polarize the laser beam parallel to the plane of incidence only light with the correct polarization will leave and re-enter the frequency selective cavity with minimum loss. The quartz crystal 28 rotates the plane of polarization of light by amounts depending on the frequency, Figs. 3, 4 (not shown), and in operation the D.C. source 31 is varied so that the electro-optic rotator rotates the selected frequencies polarization by an amount so that the polarization of the light emerging from the quartz rotator 28 is again in the plane of incidence. The selected frequency passes through cavity 27 without loss, whereas adjacent frequencies are not rotated by the rotator 29 by the correct amount to compensate for the rotation by crystal 28 and their losses are too great for lasing to occur at these frequencies. In a second arrangement, Fig. 6, the linearly polarized beam is passed through a phase plate whose phase shift is a function of the light frequency. The argon or other ionized gas laser tube 40 is arranged in the optical cavity 45, 46 together with a gypsum phase plate 47, an electro-optic phase crystal 48 and a polarizing calcite crystal 49. The linearly polarized light from laser tube 41 is converted into elliptically polarized light by phase plate 47 which ellipticity is a function of light wavelength which light will also suffer losses in passing through the Brewster windows and will not lase. The electro-optical crystal 48 imparts substantially the same phase shift to all wavelengths of light but the amount of shift is a function of the electric field across the plate. The wavelength to lase is selected by varying the electric field across plate 48 so that the phase shift introduced thereby compensates for the phase shift of the selected wavelength produced by plate 47 and this wavelength will pass through polarizer 49 without loss. However, all other lines will remain elliptically polarized and will suffer losses passing through 49 and will not lase. Polarizer 49 may be omitted in certain cases. Plates 47, 48, 49 may be replaced by a single electro-optic phase plate. Two laser lines may be selected by using two phase plates and two electro-optic phase plates in addition to a polarizing crystal which are inserted in the laser cavity, Fig. 8 (not shown). The first wavelength is selected by arranging that the two phase plates cause a resultant phase shift of zero and applying a zero electric field to the electro-optic phase plates and a second frequency is selected by applying proper voltages to the electro-optic phase plates so that the resultant phase shift of all four plates is zero for the second selected wavelength. Two or more wavelengths may be made to lase simultaneously with this arrangement.

公开(公告)号：DE2001668A1

公开(公告)日：1970-07-23

申请号：DE2001668

申请日：1970-01-15

Applicant: IBM

Inventor： JEROME HARRIS THOMAS

IPC: G02B27/00 ,  G02B27/22

Abstract: 1,252,480. Optical apparatus. INTERNATIONAL BUSINESS MACHINES CORP. Dec.30, 1969 [Jan.15, 1969], No.63206/69. Heading G2J. Dispersion compensating apparatus for resolving resolving multiple images resulting from aberration dispersions caused by manipulating a multiwavelength radiation beam using a multistage polarization deflector system, comprises in series an input 43, 44, 45, first dispersion compensating means 22, focusing means, second dispersion compensating means 23 and an output 24 wherein each dispersion compensating means is arranged to relatively alter the lengths of the paths tranversed by the various wavelengths during passage therethrough, one dispersion compensating means being arranged to resolve transverse dispersion and the other dispersion compensating means being arranged to resolve longitudinal dispersion. Each compensating means 22, 23 is formed of a plurality of stages 30-31, 32-33, 40, 41-42 equal to one less than the number of wavelengths in the beam. Each stage comprises a birefringent means 31, 33, 40 or 42 preceded by a polarization rotator 30, 32, or 41, except for the first stage 40 of compensator 23 which receives a polarized input from birefringent means 33. The input 43, 44, 45 comprises separate images of different sizes of the same object due to dispersions caused by the different wavelengths. Thus each rotator selectively rotates the polarization of selected ones of the wavelengths and each birefringent means presents different optical path distances for the wavelengths dependent upon their polarization. In this way compensator 22 forms an output of images of identical size albeit still separated; this is the input for compensator 23 which ensures that all the images being its output 24 lie in the same plane - i.e. at the focus of the lens lying between the two compensators. The rotators may be quartz crystals and the birefringent devices calcite crystals.

公开(公告)号：DE1805330A1

公开(公告)日：1969-10-23

申请号：DE1805330

申请日：1968-10-25

Applicant: IBM

Inventor： FLEISHER HAROLD ,  JEROME HARRIS THOMAS ,  MAX ERHARD

IPC: G02B5/30 ,  G02F1/29 ,  G02F1/26

公开(公告)号：DE1815841A1

公开(公告)日：1969-08-21

申请号：DE1815841

申请日：1968-12-19

Applicant: IBM

Inventor： FLEISHER HAROLD ,  JEROME HARRIS THOMAS

IPC: G11C13/04

Abstract: 1,190,184. Read-only stores. INTERNATIONAL BUSINESS MACHINES CORP. 14 Jan., 1969 [15 Jan., 1968], No. 2043/69. Heading G4A. A data processing system includes an optical memory plane storing a matrix of blocks of bits, and a plurality (e.g. three or two) of matrices of lenses, arranged in series to pass light from an illuminated block, the product of the numbers of lenses in the matrices equalling the number of blocks. The required block of bits, stored in transparent/opaque form, is illuminated with linearly-polarized laser light through a digital light deflector, the matrices of lenses passing the transmitted light to an optical AND gate at which each " transparent " bit of the word to be read out changes the polarization of light from a digital light deflector used to select the word so that the light will pass through a lens array and analyser to an array of photodetectors. A bit can be recorded on the memory plane by passing light, positioned by a digital light deflector, in the reverse direction through the lens matrices, each of which has an associated matrix of electro-optic switches and analyser to direct the bit to only one block, diffusing screens and an automatic photographic emulsion developing system being also provided (in situ). The memory plane could alternatively be a Lippmann film in which case read-out is by reflection using laser light of a frequency selected by an electro-optic frequency selector and positioned by a digital light deflector, or the plane could be metal reflecting spots on glass.

公开(公告)号：DE1514034A1

公开(公告)日：1969-08-21

申请号：DE1514034

申请日：1965-07-23

Applicant: IBM

Inventor： JEROME HARRIS THOMAS ,  ERHARD MAX DR

IPC: H01S3/06 ,  H01S3/101 ,  G02F1/24

公开(公告)号：DE1288829B

公开(公告)日：1969-02-06

申请号：DEI0026705

申请日：1964-10-15

Applicant: IBM

Inventor： JEROME HARRIS THOMAS

IPC: B41J2/435 ,  G02F1/31 ,  G06K15/12 ,  G09G3/04

Abstract: 1,012,430. Photographic type-composing. INTERNATIONAL BUSINESS MACHINES CORPORATION. Oct. 9, 1964 [Oct. 21, 1963], No. 41222/64. Heading B6W. [Also in Divisions G2 and H3] Characters formed as transparent areas in an otherwise opaque plate 4, Fig. 1, and arranged in eight columns and eight rows, are selectively projected on to a light-sensitive member 7. A light beam is passed through a lens which collimates it, the collimated beam having a crosssectional area slightly larger than that of each character on the plate 4 and being in alignment with the bottom right-hand character, and then through a device which polarizes it in a horizontal plane. The beam is then passed through a first deflector 2 which displaces it vertically and horizontally into alignment with the selected character, and then through the character, the beam then having a cross-section the same as that of the character. A second deflector 5 then restores the beam to its original alignment. A third deflector 6 displaces the beam into alignment with a selected area of the member 7. For printing lines of characters, the deflector 6 produces only horizontal displacement the member 7 being displaced vertically after each line. At least the first two deflectors each comprise a vertical and a horizontal displacement unit, the vertical unit coming first in the deflector 2 and last in the deflector 5. The vertical unit of the deflector 2 comprises birefringent crystals 24, 25, 26, Fig. 5, each of which pass light through undeflected when polarized in a horizontal plane and deflect it when polarized in a vertical plane. The deflection occurs at the entry face of the crystal and is reversed at the exit face, resulting in a vertical displacement. The unit also comprises three electro-optic devices 27, 28, 29, each consisting of a central electro-optic crystal between a pair of transparent electrodes. When a sufficient electric potential is applied between the electrodes, the crystal rotates the plane of polarization of light passing through through 90 degrees. Potential is applied selectively to the devices 27, 28, 29 by closing switches 36, 37, 38, which may be mechanical switches or electronic devices responsive to coded electric pulses. The amount of displacement by each birefringent crystal is proportional to its thickness, and the thickness of the crystals 24, 25, 26 is arranged in a binary series, so that the light emerging from the unit can be on any of eight levels. The light then passes through the horizontal unit comprising crystals 46, 47, 48, the vertical and horizontal units being viewed in directions at right-angles to each other in Fig. 5. The beam then passes through the selected character in the plate 4 and through the horizontal and vertical units of the deflector 5, which are shown at the lower part of Fig. 5 as comprising respectively crystals 58, 57, 56 and 66, 65, 64. The units of the deflector 5 are viewed in Fig. 5 from the opposite direction as compared with those of the deflector 2, the light actually passing in the same general direction through all four units. In the case of the deflector 5, the light passes through the thickest crystal first in each unit and through each crystal before its associated electro-optic device. Each pair of electro-optic devices, i.e. the first (27) in the vertical unit of the deflector 2 and the last (67) in the vertical unit of the deflector 5 and so on as shown, are connected so as to be activated by a common switch 36, 37, 38, 52, 53, 54. The result of this arrangement is to restore the beam to its original alignment polarized in a horizontal plane as before. The units of the deflector 6 are the same as those described above, except that each may have more than three crystals and electro-optic devices, and that the horizontal unit may be omitted. In another form, Fig. 8 (not shown), the deflector 6 is replaced by a mirror continuously rotating about a vertical axis and co-operating with an electro-optic shutter opened at the appropriate time to project the character at the desired horizontal position on the member 7, the latter being shifted vertically after each line. In another form, Fig. 7, a beam of polarized light 81 from a source 82 is directed on to a beam splitter 83 consisting of a pair of sodium nitrate crystals 84, 85 arranged face to face and at an angle of 45 degrees to a vertical plane, and is deflected as shown as a beam polarized at 45 degrees to a vertical plane to a light rotator 87, from which it emerges polarized in a horizontal plane. Vertical and horizontal displacement units 88, 89 direct it to a selected character formed as a reflecting area on a screen 90, whereby it is reflected back through the units 89, 88 into its original alignment and through the rotator 87, which rotates its plane of polarization 45 degrees so as to be at right-angles to its original plane of polarization. The beam now passes through the beam splitter 83 without deflection to a quartz plate 92 from which it emerges polarized in a hori- ,zontal plane. The beam now passes through a lens 93 which sharpens the outline of the beam and inverts the character, vertical and horizontal displacement units 94, 96, and an inverting and magnifying lens 96 to the medium 7. In another form, Fig. 6, a light beam is produced during a lasing action by reflecting light through a negative temperature unit 72 from a fully reflecting mirror 78 and a partly reflecting mirror 73 at the ends of the unit 72. At one end of the unit 72, the optical cavity includes vertical and horizontal displacement units 76, 77, and the mirror 78 comprises reflecting areas formed in the shape of characters. Light passing through the units 76, 77 is brought into alignment with the selector character and on passing back through the units 77, 76 is restored to its original alignment, then passing as a collimated and plane polarized beam through the mirror 73 and vertical and horizontal displacement units 21, 22 to the medium 7. Specification 992,452 is referred to.