Eyesafe erbium glass microlaser

Abstract

A miniature diode pumped Er,Yb:glass laser has been developed at the Night Vision and Electronic Sensors Directorate, U. S. Army CECOM (NVESD) for soldier applications. This device uses a single laser diode at 925 nm to end pump a 200µmφ x 3 mm volume of Er,Yb:glass gain media. A Co 2+ :MgAl 2 O 4 passive Q-switch is used to produce 2 nanosecond pulses at a repetition rate from single shot to 20 Hertz. A nominal pulse energy of 100 microjoules is emitted, corresponds to a peak power of 50 kilowatts, which is sufficient for ranging to over 2 kilometer. The Eyesafe Microlaser was designed and demonstrated to operate over a wide temperature range without temperature control of the pump laser, a feature important for soldier applications. An desirable feature of Er,Yb:glass lasers is that they emit directly at 1.54 microns, which is important for eye safe operation and low cost fabrication.

Modeling a diode pumped Er:Yb:glass laser with Co2+:spinel as a passive Q-switch

“…Using Kigre's QX/Er 16 phosphate glass with custom doping concentrations, Hamlin and co-workers report nominal pulse energies of 100 µJ, peak powers of up to 50 kW, and pulse widths of 2 ns. [12][13][14] In order to facilitate a semi-quantitative comparison with experimental data three key assumptions were made: 1) the pump mode diameter is taken to be 254 µm, 2) the laser mode diameter is taken to be 140 µm, and 3) no spatial variation of the pump and laser mode in the gain medium. A summary of the comparison is given in Table 1.…”

Progress in Nd3+, Er3+, and Yb3+ doped laser glasses at Shanghai Institute of Optics and Fine Mechanics

“…32,33 Er 3+ -doped glass is the only laser gain media that has demonstrated direct generation of laser radiation near the 1.55 lm "eye-safe" wavelength band at reasonable efficiency. 34 Q-switched, solid-state erbium lasers at~1.55 lm is an "eye-safer" coherent source for laser sensing, 35 velocimetry, 36 detection of atmosphere pollution, 37 ultrasound imaging, 38 range finding, 39 medical application, 40 and laser-induced breakdown spectroscopy (LIBS). 41 Properties of Er 3+ ions in different glass hosts have been widely investigated, especially for phosphate glasses.…”

“…For the former, Ce 3+ and Cr 3+ are co‐doped with Er 3+ for better absorption of flash lamp pumping . Er 3+ ‐doped glass is the only laser gain media that has demonstrated direct generation of laser radiation near the 1.55 μm “eye‐safe” wavelength band at reasonable efficiency . Q‐switched, solid‐state erbium lasers at ~1.55 μm is an “eye‐safer” coherent source for laser sensing, velocimetry, detection of atmosphere pollution, ultrasound imaging, range finding, medical application, and laser‐induced breakdown spectroscopy (LIBS) .…”

Material and Ingenious Synthesis Strategy for Short-Wavelength Infrared Light-Emitting Device

“…Infrared light-emitting materials continue to be of significant interest to scientists, due to their wide applications in biological imaging, optical fiber communication, silicon-based solar cell, laser crystal, , military, and so forth. Especially, the material with emission around 1500 nm (short-wavelength infrared, SWIR) has a special fascination, not only because the wavelength is in the third low-loss window for optical fiber communication, but also according to the latest investigations it is in the second “tissue-transparent window” for in vivo optical imaging for disease screening and image-guided surgical interventions in biomedical field. , Additionally, the 1500 nm SWIR is in the eye-safe wavelength range.…”