1. Field of the Invention
The present invention relates to an optical sensor and a thermal sensor.
2. Description of the Prior Arts
Many kinds of thermal sensors and optical sensors having a structure where a thermosensitive material and a photosensitive material are applied to the surface of paper, film, etc. have already been put to practical use and are being used. Moreover, there are many types of mediums in the form of thermosensitive paper and photosensitive paper for recording and displaying images such as letters, figures, etc.
However, few of the conventional sensors meet a demand for a sensor having an excellent sensitivity, being easily manufactured and whose characteristic is stably maintained.