Optical information reader

Abstract

Abstract PURPOSE: To secure the reading for the information written by almost all kinds of writing tools by using the fluorescent lamp the light emission wavelength of which is within the specified range for the light source. CONSTITUTION: Information 4 written on paper 3 is irradiated via light source 10, and the reflected light beams from the paper surface are condensed to the light emitting element 2 through lens 5. In such constitution, the fluorescent lamp which features the peak of the light emission wavelength set within 6000W7500Å along with the half-value width of 500Å or less and uses the fluorescent substance of magnesium arsenate is used for light source 10. For the spectral reflection factor properties of the writing tools, both the black pencil and black ball pen feature the sufficiently low reflection factor at 6000W7000Å; while paper 4 features the sufficiently high reflection factor respectively. Furthermore, for the spectral sensitivity properties of the Si photo diode used for element 2, the relative sensitivity of about 80% is obtained with 6580Å. Thus the information written by almost all kinds of black writing tools can be read out in a high speed. COPYRIGHT: (C)1980,JPO&Japio

Inventors

• 👤 Hajime Nanbu
• 👤 Taketo Toyoda
• 👤 Hidekazu Noguchi
• 👤 Yoshinori Anzai
• 👤 Masaru Kamimura

Bibliographic Details