To analyze optical sources with time‐varying spectra, an optical transient spectrum analyzer (OTSA) with high time resolution is developed. In the spectrum analyzer, the dispersive light is focused on the CCD by a lens and each pixel of the CCD is made to correspond to one spectrum line. It is possible to realize wavelength resolutions between 0.2 and 0.63 nm by changing the optical elements. Variations of extraction pixels of CCD allow time resolutions between 23 μs and 1 ms. Therefore, various applications (such as optical source analyzing systems) are expected. The data from CCD are A‐D transformed and stored in a floppy disk. Therefore, it becomes possible to discuss the characteristics of the optical sources quantitatively. Finally, as an example, the transient mode‐hopping phenomenon of a semiconductor laser is time resolved with high speed and its three‐dimensional (3‐D) observation is presented.
|Number of pages||9|
|Journal||Electronics and Communications in Japan (Part II: Electronics)|
|Publication status||Published - 1990|
ASJC Scopus subject areas
- Physics and Astronomy(all)
- Computer Networks and Communications
- Electrical and Electronic Engineering