Fig. 1. Simulation results of optical path structure along different directions. (a) Fast axis direction; (b) slow axis direction

Fig. 2. Schematic of light path structure

Fig. 3. Laser ignition window based on grin lens

Fig. 4. Divergence angles of optical fiber spot under different output conditions. (a) Free running; (b) by self-focusing lens collimating

Fig. 5. Laser power after beam shaping and fibre coupling. (a) 976 nm laser; (b) 1310 nm laser

Fig. 6. Photograph of laser ignition light source

Fig. 7. P-I -V curves of 976 nm laser

Fig. 8. Light spots before and after shaping via self-focusing lens. (a) Before shaping; (b) after shaping

Fig. 9. Curves obtained in this experiment. (a) P-I -V curves of 1310 nm laser; (b) response current and responsivity of detection light

Fig. 10. Response current of detection light for 976 nm laser