We demonstrate a home-made two-photon laser scanning microscopy (TPLSM) with a light stimulus system. In this system, the femtosecond pulses are produced by a picosecond fiber laser with pulse width compression. A laser diode serves as stimulus, which modulated by an AOM and coupled into the same light path of a femtosecond laser. The control signal of AOM and trigger signal of two scanning mirrors are synchronized by a FPGA board. With modulating the intensity of CW laser at precise point in one scanning frame, any pattern of light stimulus can be delivered to the sample in real time.
We design a real-time laser stimulus system for laser confocal scanning microscope. By introducing the FPGA and AOM to achieve high speed modulation of a scanning laser, we can adjust the laser lighting area freely. For reducing the size of the optical path, we use MEMS-mirror instead of traditional fast and slow axis mirrors. The size of MEMS-mirror is 1.5 mm diameter and the scanning frequencies are set 16 kHz and 12 Hz at the fast and slow axis, respectively. Our system is capable of delivering stabilized large stimulus pattern (up to 500 x 500 pixels) to the biological tissues.