A 658-W VCSEL-pumped rod laser module with 52.6% optical efficiency

Abstract

A high-efficiency and high-power vertical-cavity surface-emitting laser (VCSEL) side-pumped rod Nd:YAG laser with temperature adaptability is demonstrated. The VCSEL side-pumped laser module is designed and optimized. Five VCSEL array is symmetrically located around the laser rod and a large size diffused reflection chamber is designed to ensure a uniform pump distribution. Furthermore, the absorbed pump power distribution of the rod is simulated to verify the uniformity of the pump absorption. Finally, a proof-of-principle experiment is performed in short linear cavity laser with single laser module. A continuous-wave output power of 658 W at 1064 nm is obtained, the corresponding optical-to-optical efficiency is 52.6%, and the power variations are ± 0.7% over 400 s and ± 3.1% over the temperature range from 16℃ to 26℃. To the best of our knowledge, this is the highest output power and the highest optical-to-optical efficiency ever reported for VCSEL pumped solid-state lasers. By inserting a telescopic module into the cavity and optimizing the TEM00 mode volume, the average beam quality is measured to be M 2=1.34 under an output power of 102 W. The experimental results reveal that such a high power rod laser module with temperature stability is appropriate for field applications.

Continuous wave and active Q-switched operation of Watt-level LED-pumped two-rod Nd,Ce:YAG laser

“…And the experimentally measured thermal focal length value is greater than 3 m. Combined with the measured thermal focal length value and theoretical analyses of laser cavity mode, it can be concluded that the marked ranges a and b correspond to the power-stable region and mode-stable region within LEDpumped CW solid-state laser's optimal working stability zone, while the marked mode-stable region c and power-stable region d within the traditional LD-pumped CW solid-state laser are optima work stability zone. [19][20][21][22][23][24][25]25] Due to the thermal accumulation from LED CW pumping, the temperature difference between the crystal's interior and thermal distortion gradually increase, resulting in a transition from range a to range b in the laser stable area. Moreover, the value of thermal focal length gradually becomes smaller, and the value of the fundamental mode spot radius ω 0 and mode volume also decreases accordingly.…”

Small air-cooled, heat-dissipating VCSEL end-pumped disc laser design

“…Conventional side-emitting diode lasers have large differences in fast and slow axis divergence angles, elliptical output spots, complex beam shaping systems [2] , and are sensitive to temperature changes, with a temperature drift coefficient of 0.3 nm/°C [3] at the central wavelength, and require an additional temperature control system when used in environments with large temperature changes. Compared to traditional side-emitting semiconductor lasers, VCSEL has high beam quality, the output light is a circular spot with a small divergence angle, are insensitive to temperature variations, have a small temperature drift coefficient, with a temperature drift coefficient of 0.06nm/°C [4] at the centre wavelength, and do not require additional temperature control systems when used in environments with large temperature variations. A VCSEL array contains hundreds or thousands of units, through the two-dimensional array arrangement can achieve high power output, so the VCSEL is suitable as a compact high-power solid state laser pump source [5][6][7] .…”

An LED-Side-Pumped Intracavity Frequency-Doubled Nd,Ce:YAG Laser Producing a 2W Q-Switched Red Beam

“…DOI: 10.1088/0256-307X/41/3/034201 The 1.3 µm laser is currently valuable in research as a pump source in oscillator power amplifiers and fibre Raman amplifiers, and was also utilized to obtain highpower red laser outputs by frequency doubling. [1][2][3][4][5] In recent years, in virtue of the low-cost and miniaturization of light-emitting diodes (LEDs), and the significant enhancement of power, the medium bandwidth pumping generated by LEDs was expected to be an option for cost-effective lasers. We envisaged a scheme for a novel LED-pumped all-solid-state laser to generate 1.3 µm lasers.…”