摘要 |
A laser radar transmitter (2) has, associated with a single active lasing region (11) and preferably in the same laser cavity (1) therewith, an amplitude modulator (21) and a frequency modulator (25), which may simultaneously place continuous AM and continuous FM on a single output beam (7). Amplitude modulator (21) is preferably an EO crystal having a high EO coefficient, low loss, and field-induced birefringence. Frequency modulator (25) is preferably an EO crystal having a high EO coefficient, low loss, and a field-induced index change. Applying a d.c. driving voltage to the AM crystal (21) and an a.c. driving voltage to the FM crystal (25) produces an output beam (7) having FM. Applying an a.c. driving voltage to the AM crystal (21) produces an output beam (7) having AM, independently of whether FM is added by means of applying an a.c. driving voltage to the FM crystal (25).
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