Author(s): Micah Laing, Benjamin Holt
Mentor(s): York E. Young
Institution UVU
An advanced optical system that generates tunable longwave infrared (LWIR) light is being developed by our research group, aimed at the early detection of disease-indicating molecules in human tissue. At the core of this system, a newly constructed Nd:YVO4 laser produces between five and seven watts of continuous wave optical power in the near-infrared (IR) spectrum. This laser serves as the optical drive for the nonlinear optical subsystem responsible for generating LWIR light via an optical parametric oscillator. To achieve wavelength conversion via non-linear processes, the near-IR laser power must reach intensities on the order of tens of megawatts per square centimeter (MW/cm²). Such high intensities are attained by concentrating the laser power into high-intensity nanosecond class pulses through Q-switching. An acousto-optic modulator will be implemented within the laser cavity to achieve effective Q-switching. The circuitry required to run the RF driver that powers the modulator has been assembled, and testing of the Q-switch with a visible red HeNe laser is underway. This test will determine the RF power needed to deflect roughly 80% of the beam’s power into the first order of diffraction, providing a baseline for adjustments necessary for the Nd:YVO4 laser setup. The design and assembly of the modulator's kinematic mount, cooling system, and RF driver, as well as the performance characterization of the modulator for laser Q-switching, will be detailed in this presentation.