Information reading method
First Claim
Patent Images
1. An information reading method comprising the steps of:
- irradiating a phosphor activated by neodymium and ytterbium ions with exciting light having a wavelength from 500 nm to 780 nm that can excite the neodymium ions; and
reading the information by receiving the light emitted from the phosphor with a photodetector sensitive to light within a wavelength range from about 840 nm to about 1100 nm.
1 Assignment
0 Petitions
Accused Products
Abstract
An information reading method includes the steps of irradiating a phosphor activated by neodymium and ytterbium ions with exciting light of a wavelength between 500 nm and 780 nm that can excite the neodymium ions, and reading the information by receiving the light emitted from the phosphor with a photodetector designed to detect light with wavelengths between 840 m and 1100 nm. Consequently, the information recorded using the phosphor activated by neodymium and ytterbium ions can be read with a high performance without using a filter for cutting the exciting light.
23 Citations
13 Claims
-
1. An information reading method comprising the steps of:
-
irradiating a phosphor activated by neodymium and ytterbium ions with exciting light having a wavelength from 500 nm to 780 nm that can excite the neodymium ions; and reading the information by receiving the light emitted from the phosphor with a photodetector sensitive to light within a wavelength range from about 840 nm to about 1100 nm. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
-
-
13. An information reading method comprising the steps of:
-
irradiating a phosphor activated by neodymium and ytterbium ions with exciting light having peak wavelengths below 780 nm that can excite the neodymium ions; and reading the information by receiving the light emitted from the phosphor with a photodetector sensitive to light within a wavelength range from about 840 nm to about 1100 nm.
-
Specification