Optical information reproduction by irradiating two laser beams into a recording medium of at least three energy levels and detecting absorption or photoluminescence
US5754511A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 13, 1996 |
| Grant date | May 19, 1998 |
| Priority date | — |
| Expiry date | Sep 13, 2016 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S977/951
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
There is provided an optical detection method comprising the steps of preparing a solid body having an energy level structure constituted by at least three energy levels, and irradiating first and second coherent light on the solid body to optically detect the physical structure of the solid body, wherein the detection step satisfies the following conditions: PA1 min(.epsilon..sub.i31)<h.omega..sub.p /2.pi.<max(.epsilon..sub.i31), PA1 min(.epsilon..sub.i32)<h.omega..sub.c /2.pi.<max(.epsilon..sub.i32), and PA1 h.OMEGA..sub.c /2.pi.<max(.epsilon..sub.i31)-min(.epsilon..sub.i31) where the number of physical structures included in the solid body is N, the predetermined three levels of ith physical structure are called first, second, and third levels, and energies of the first, second, and third levels are .epsilon..sub.i1, .epsilon..sub.i2, and .epsilon..sub.i3, respectively, of the N physical structures, the maximum value of .vertline..epsilon..sub.i3 -.epsilon..sub.i1 .vertline. is max(.epsilon..sub.i31), and the minimum value is min(.epsilon..sub.i31), of the N physical structures, the maximum value of .vertline..epsilon..sub.i3 -.epsilon..sub.i2 .vertline. is max(.epsilon..sub.i32…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.