Method of operating an information storage tube

Claim 3

means including a cathode for producing an electron beam and for scanning said beam over said target; and

Claim 4

means including a cathode for producing an electron beam and for scanning said beam over said target; and

Claim 5

means including a cathode for producing an electron beam and for scanning said beam over said target; and

Claim 6

means including a cathode for producing an electron beam and for scanning said beam over said target; and

Claim 7

The method defined in claim 1, wherein said substrate potential in step (a) is at least 10 volts positive with respect to said cathode.

Claim 8

The method defined in claim 1, wherein said conducting layer potential in step (a) is about 5 volts positive with respect to said cathode.

Claim 9

means for collecting secondary electrons emitted by said storage layer; said method comprising the following steps: a. applying to said substrate a low positive potential below the first cross-over potential of the secondary emission curve for said storage layer material, and applying to said conducting layer a positive potential lower than said substrate potential; and b. scanning said target with an unmodulated low-velocity priming beam, to reduce the potential of said storage layer substantially to the potential of said conducting layer.

Claim 10

means for collecting secondary electrons emitted by said storage layer; said method comprising the following steps: a. applying to said substrate a low positive potential below the first cross-over potential of the secondary emission curve for said storage layer material, and applying to said conducting layer a positive potential lower than said substrate potential; and b. scanning said target with an unmodulated low-velocity priming beam, to reduce the potential of said storage layer substantially to the potential of said conducting layer.

Claim 11

means for collecting secondary electrons emitted by said storage layer; said method comprising the steps of: a. applying to said substrate a given low positive potential below the first crossover potential of the secondary emission curve for said storage layer, and applying to said conducting layer a positive potential a few volts lower than said substrate potential; and b. scanning said target with an unmodulated low velocity priming beam to reduce the potential of said storage layer substantially to the potential of said conducting layer; c. then repeating steps (a) and (b), with successively higher substrate potentials and substantially the same conducting layer potential, until the difference between the potential of said substrate and the common potential of said storage layer and said conducting layer is about 25 volts; d. then reducing the potential of said substrate to a value substantially equal to said difference, and increasing the potential applied to said conducting layer to substantially the same value, to produce the condition wherein all portions of said substrate are substantially at zero potential and said substrate and conducting layer are at suitable positive potentials preparatory to a writing operation; e. then increasing the potential applied to said substrate and to said conducting layer to a potential within the secondary electron emission range of said storage layer material, and applying a higher potential to said collecting means; and f. scanning said target with a modulated high velocity writing beam embodying the information sought to be stored for a time sufficient to produce an electrostatic charge pattern on said storage layer.

Claim 12

means for collecting secondary electrons emitted by said storage layer; said method comprising the steps of: a. applying to said substrate a given low positive potential below the first crossover potential of the secondary emission curve for said storage layer, and applying to said conducting layer a positive potential a few volts lower than said substrate potential; and b. scanning said target with an unmodulated low velocity priming beam to reduce the potential of said storage layer substantially to the potential of said conducting layer; c. then repeating steps (a) and (b), with successively higher substrate potentials and substantially the same conducting layer potential, until the difference between the potential of said substrate and the common potential of said storage layer and said conducting layer is about 25 volts; d. then reducing the potential of said substrate to a value substantially equal to said difference, and increasing the potential applied to said conducting layer to substantially the same value, to produce the condition wherein all portions of said substrate are substantially at zero potential and said substrate and conducting layer are at suitable positive potentials preparatory to a writing operation; e. then increasing the potential applied to said substrate and to said conducting layer to a potential within the secondary electron emission range of said storage layer material, and applying a higher potential to said collecting means; and f. scanning said target with a modulated high velocity writing beam embodying the information sought to be stored for a time sufficient to produce an electrostatic charge pattern on said storage layer.

Claim 13

The method defined in claim 1, wherein said conducting layer potential is applied in a single step, and said substrate potential is gradually applied, said gradual application being done simultaneously with said scanning of said target with said priming beam.

Claim 14

The method defined in claim 4, wherein said gradual application of said substrate potential is carried out in a series of consecutive step-wise voltage increments.

Claim 15

The method defined in claim 5, wherein after the last of said voltage increments, the difference between the potential of said substrate and the common potential of said conducting layer and said storage layer is about 25 volts.

Claim 16

The method defined in claim 6, comprising the subsequent step of reducing the potential applied to said substrate to a value equal to said difference thereby reducing the potential of said storage layer substantially to zero.

Claim 19

The method defined in claim 8, comprising the subsequent steps of: a. reducing the potential applied to said substrate and to said conducting layer to a potential such that the maximum electrostatic charge potential of said storage layer portions is substantially equal to zero; and b. scanning said target with an unmodulated low velocity reading beam, the landing of the electrons on said conducting layer being modulated by said electrostatic charge pattern, thereby producing a non-destructive information output to said conducting layer.

Claim 20

The method defined in claim 8, comprising the subsequent steps of: a. increasing the potential applied to said substrate and said conducting layer to a given positive potential such that all of the elemental potentials of said storage layer are raised by capacitive coupling to values within the secondary emission range, and applying to said secondary electron collecting means a positive potential at least as high as that applied to said substrate; and b. scanning said target with an unmodulated high velocity erasing mean for a time sufficient to raise the potential of all portions of said storage layer substantially to the potential of said substrate; and c. then removing all of said potentials.