Optical magnifiers, also known as magnifying glasses, are essential tools for enhancing visual perception. Employing convex lenses, they enlarge objects, making details more discernible to the human eye. Widely used in various fields such as reading, inspection, and hobbyist activities, these magnifiers come in diverse shapes and sizes to suit different needs. Choose a type of optical magnifiers below.

Nonlinear crystalexamples

Gallium Selenide (GaSe) non-linear optical single crystal, combining a large non-linear coefficient, a high damage threshold and a wide transparency range. It is a is very suitable material for SHG in the mid-IR.

Non linear opticalcrystal

AGS is transparent from 0.50 to 13.2 µm. Although its nonlinear optical coefficient is the lowest among the mentioned infrared crystals, high short wavelength transparency edging at 550 nm is made use of in OPOs pumped by Nd:YAG laser; in numerous difference frequency mixing experiments with diode, Ti:Sapphire, Nd:YAG and IR dye lasers covering 3–12 µm range; in direct infrared countermeasure systems, and for SHG of CO2 laser. Thin AgGaS2 (AGS) crystal plates are popular for ultrashort pulse generation in mid IR range by difference frequency generation employing NIR wavelength pulses.

ZGP crystals possess large nonlinear coefficients (d36=75pm/V), wide infrared transparency range(0.75-12μm), high thermal conductivity(0.35W/(cm·K)), high laser damage threshold (2-5J/cm2)and well machining property, ZnGeP2 crystal was called the king of infrared nonlinear optical crystals and is still the best frequency conversion material for high power, tunable infrared laser generation. We can offer high optical quality and large diameter ZGP crystals with extremely low absorption coefficient α < 0.02 cm-1(at pump wavelengths 2.0-2.1 µm), which can be used to generate mid-infrared tunable laser with high efficiency through OPO or OPA processes.

Nonlinear crystalmeaning

LGS is a new type of mid-infrared nonlinear crystal. LiGaS2 has excellent properties such as wide band gap, low two-photon absorption, wide transparent range, small group velocity mismatch, high thermal conductivity, and low thermal expansion coefficient.

High-quality crystals of BGSe (BaGa4Se7) is the selenide analogue of the chalcogenide compound BaGa4S7, whose acentric orthorhombic structure was identified in 1983  and the IR NLO effect was reported in 2009, is a newly developed IR NLO crystal. It was obtained via the Bridgman–Stockbarger technique. This crystal exhibits high transmittance over the wide range of 0.47–18 μm, except for an absorption peak at around 15 μm.

AGSe AgGaSe2 crystals have band edges at 0.73 and 18 µm. Its useful transmission range (0.9–16 µm) and wide phase matching capability provide excellent potential for OPO applications when pumped by a variety of different lasers. Tuning within 2.5–12 µm has been obtained when pumping by Ho:YLF laser at 2.05 µm; as well as non-critical phase matching (NCPM) operation within 1.9–5.5 µm  when pumping at 1.4–1.55 µm. AgGaSe2 (AgGaSe2) has been demonstrated to be an efficient frequency doubling crystal for infrared CO2 lasers radiation.