Picosecond laser pump source - Ultrafast laser pump source - Picosecond optical parametric oscillator OPO Product description:

FPPO ps is a picosecond laser pump source ultrafast laser pump source picosecond optical parametric oscillator (OPO) suitable for Raman imaging and spectroscopy. The system is driven by a fiber laser with a pulse time of 6ps, a wavelength of 1064 nm, and a repetition rate of 110 MHz. By converting the second harmonic to 532 nm and using the 532nm pulse as the pump for OPO, the output pulse signal can be adjusted between 720-1000nm (signal) and 1150-1800nm (idle frequency). FPPO is the first commercial fiber laser pumped OPO system designed specifically for CARS imaging. The FPPO output consists of three independent beams: a signal beam (720-1000nm tunable), a idler beam (1150-1800nm tunable), and a pump laser beam fixed at 1064nm. Tuning is achieved by adjusting the crystal temperature, cavity length, and cavity filter. Using 1064nm light as Stokes light and OPO signal light as pump light, Raman modes ranging from 600 cm-1 to 4200 cm-1 can be detected. The typical output power of signal light is 250-700mW, while that of idler light is 100-400mW. However, if higher power is required, higher power fiber lasers can be used for pumping.

In the CARS experiment, a tunable signal beam was used as the pump, providing Stokes pulses at a fundamental value of 1064nm. Users can also use longer wavelength idler pulses. Short duration (<6 ps) and narrow bandwidth (<10 cm-1) provide peak power and spectral selectivity, which are essential for CARS imaging and spectroscopy.

Microtech product structure diagram:

In harmonic crystals, the fiber laser at 1064nm is partially converted to 532nm, which can serve as a pump for OPO. OPO resonates with the signal beam, and the idler light is transmitted through the cavity mirror. The FPPO output includes signal light, idler beam, and inexhaustible pump.

Microtech technical specifications:

• Pulse width:< 300fs
• Bandwidth:> 50 cm^-1
• Time bandwidth product:~ zero point six
• Output power: 100-800mW
• Center wavelength:

1. 720-1000nm (signal light)
2. 1150-1800nm (idle frequency light)
3. 1064nm fiber pump

• Beam quality M²：< one point three
• Polarization: Linear horizontal polarization
• Repetition frequency: 110MHz
• Beam diameter: 1mm

Tuning range:

The blue curve in the figure represents the signal light output, and the red curve represents the idle frequency light output. Tuning is achieved by changing the crystal temperature and cavity length.

Pulse characteristics:

The following figure shows the autocorrelation (left) and spectral curve (right) of a 830.5nm signal pulse. It can be seen from the figure that the typical bandwidth of this pulse is 0.5nm and the pulse time is 5ps

Beam characteristics:

The following figure shows the beam profile of a 1mm diameter beam, with a Gaussian distribution: