| 摘要 |
PROBLEM TO BE SOLVED: To obtain a high efficiency optical filter (BPF) easy to design and produce by providing left-right asymmetry to a spectral transmittance characteristic curve in a coordinate system with wavelength as the x-axis and transmittance as the y-axis. SOLUTION: This optical filter has a spectral transmittance characteristic curve having left-right asymmetry in the coordinate system with wavelengthλas the x-axis and transmittance T as the y-axis. On the shorter wavelength side, rising from the bottom to the peak is steep and the wavelength width between the bottom and peak is <=10 nm. On the longer wavelength side, transmittance lowers gradually and reaches the bottom in the range of about 20 nm. The simplest method for making a transmittance change of BPF swift is carried out by repetitive passing through films having the same characteristics, e.g. short wavelength cutting characteristics or by repetitive reflection on the films.
|
