Patent US2250473A successfully refreshed from Google Patents.
Patent US3892473A successfully refreshed from Google Patents.
US3892473A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of writing additional information in read-only memory
Assignee: Mitsubishi Electric Corp
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Filing: 1973-02-15
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Granted: 1975-07-01
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Expires: 1993-02-15
Abstract
Abstract To write an additional bit of information in a memory in the form of a phase diffraction grating formed on a transparent plastic film by stamping on the film an embossing die including a grating, the same die is first located at its angular position as determined by the bit of information measured with respect to a reference and then stamped upon the diffraction grating on the film to form a corresponding diffraction grating in superposed relationship with the preceding grating. A die may be used different in grating constant from the first die.
Inventors
- 👤 Shigeru Ando
- 👤 Kazunaru Tomishima
- 👤 Akira Nishikawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 08:03
CPC Classifications
G; G11; G11C; G11C13/00; G11C13/04
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
90 words
A method of writing an additional bit of information in a read-onLy memory, including the step of superimposing, upon a phase diffraction grating defining a memory formed on a record medium of plastic material, a separate phase diffraction grating through a plastic deformation of the plastic material due to a pressure applied to the record medium, the separate phase diffraction grating having a selected one of parameters defining the direction of diffraction as determined by an additional bit of information to be written from that of the preceding diffraction grating.
Claim 2
Independent Claim
90 words
A method of writing an additional bit of information in a read-onLy memory, including the step of superimposing, upon a phase diffraction grating defining a memory formed on a record medium of plastic material, a separate phase diffraction grating through a plastic deformation of the plastic material due to a pressure applied to the record medium, the separate phase diffraction grating having a selected one of parameters defining the direction of diffraction as determined by an additional bit of information to be written from that of the preceding diffraction grating.
Claim 3
Dependent Claim
26 words
A method of writing an additional bit of information in a read-only memory as claimed in claim 1 wherein the selected parameter is a grating constant.
Claim 4
Dependent Claim
39 words
A method of writing an additional bit of information in a read-only memory as claimed in claim 1 wherein the selected parameter is an angle of run of parallel grooves of the diffraction grating with respect to a reference.
Claim 5
Independent Claim
120 words
A method of writing an additional bit of information in a read-only memory using an embossing die having a grating including a plurality of parallel grooves, and a record medium of transparent plastic material having embossed thereon a phase diffraction grating by stamping the embossing die on the record medium, which method includes the steps of locating the embossing die above the phase diffraction grating so that the parallel grooves thereof has an angle of run as determined by an additional bit of information to be written with respect to a reference, and stamping the embossing die upon the preceding the diffraction grating on the record medium to form a corresponding phase diffraction grating superimposed on the preceding diffraction grating.
Claim 6
Independent Claim
120 words
A method of writing an additional bit of information in a read-only memory using an embossing die having a grating including a plurality of parallel grooves, and a record medium of transparent plastic material having embossed thereon a phase diffraction grating by stamping the embossing die on the record medium, which method includes the steps of locating the embossing die above the phase diffraction grating so that the parallel grooves thereof has an angle of run as determined by an additional bit of information to be written with respect to a reference, and stamping the embossing die upon the preceding the diffraction grating on the record medium to form a corresponding phase diffraction grating superimposed on the preceding diffraction grating.
Claim 7
Dependent Claim
29 words
A method of writing an additional bit of information in a read-only memory as claimed in claim 1 wherein the superimposed phase diffraction gratings are of an echelette type.
Claim 8
Dependent Claim
29 words
A method of writing an additional bit of information in a read-only memory as claimed in claim 4, wherein the superimposed phase diffraction gratings are of the echelette type.
Claim 9
Independent Claim
136 words
A method for writing additional bits of information in a read only memory of the type having an impressible recording medium and a first diffraction grating impressed thereon in a given area and having a first phase orientation with respect to the recording medium and a first diffraction angle both corresponding to a first bit of information, said method comprising: impressing a second diffraction grating on the recording medium superimposed on the first diffraction grating in said given area without impairing the effectiveness of said first diffraction grating and having a second phase orientation different from said first phase orientation and a second diffraction angle, both said second phase orientation and said second diffraction angle corresponding to a second bit of information to be written into the memory in addition to the first bit of information.
Claim 10
Independent Claim
136 words
A method for writing additional bits of information in a read only memory of the type having an impressible recording medium and a first diffraction grating impressed thereon in a given area and having a first phase orientation with respect to the recording medium and a first diffraction angle both corresponding to a first bit of information, said method comprising: impressing a second diffraction grating on the recording medium superimposed on the first diffraction grating in said given area without impairing the effectiveness of said first diffraction grating and having a second phase orientation different from said first phase orientation and a second diffraction angle, both said second phase orientation and said second diffraction angle corresponding to a second bit of information to be written into the memory in addition to the first bit of information.
Claim 11
Dependent Claim
15 words
A method according to claim 7, wherein said first and second diffraction angles are equal.
Claim 12
Dependent Claim
64 words
A method according to claim 7, further comprising the steps of impressing at least one additional diffraction grating on the recording medium superimposed on the first and second diffraction gratings and without impairing the effectiveness of said first and second diffraction gratings wherein each additional diffraction grating has a different phase orientation and a given diffraction angle corresponding to an additional bit of information.
Claim 13
Dependent Claim
42 words
A method according to claim 7, wherein said step of impressing the second diffraction grating on the first diffraction grating comprises impressing the recording medium with a die having an angular orientation corresponding to the phase orientation of said second diffraction grating.
Claim 14
Dependent Claim
16 words
A method according to claim 7, wherein said second diffraction grating comprises echelette type diffraction grating.
Claim 15
Independent Claim
142 words
An apparatus for writing bits of information in a read only memory of the type having an impressible recording medium comprising means for impressing a first diffraction grating on the recording medium in a given area and having a first phase orientation with respect to the recording medium and a first diffraction angle both corresponding to a first bit of information; and means for impressing at least a second diffraction grating on the recording medium superimposed on the first diffraction grating in said given area without impairing the effectiveness of said first diffraction grating and having a second phase orientation different from said first phase orientation and a second diffraction angle, both said second phase orientation and said second diffraction angle corresponding to a second bit of information to be written into the memory in addition to the first bit of information.
Claim 16
Independent Claim
142 words
An apparatus for writing bits of information in a read only memory of the type having an impressible recording medium comprising means for impressing a first diffraction grating on the recording medium in a given area and having a first phase orientation with respect to the recording medium and a first diffraction angle both corresponding to a first bit of information; and means for impressing at least a second diffraction grating on the recording medium superimposed on the first diffraction grating in said given area without impairing the effectiveness of said first diffraction grating and having a second phase orientation different from said first phase orientation and a second diffraction angle, both said second phase orientation and said second diffraction angle corresponding to a second bit of information to be written into the memory in addition to the first bit of information.
Claim 17
Dependent Claim
15 words
An apparatus according to claim 12, wherein said first and second diffraction angles are equal.
Claim 18
Dependent Claim
28 words
An apparatus according to claim 12, wherein said means for impressing comprises a die having an angular orientation corresponding to the phase orientation of said second diffraction grating.
Claim 19
Dependent Claim
16 words
An apparatus according to claim 12, wherein said second diffraction grating comprises echelette type diffraction grating.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-06-30 | 1978-12-30 | 1979-07-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-30 | 1982-12-30 | 1983-07-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-30 | 1986-12-30 | 1987-07-01 | $7700.00 | Window Closed / Lapsed |