Quality Assurance

The G&H Quality function incorporates site based quality management, compliance activities, process and tools and continuous improvement.

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Nonlinear Optics

Crystals and Nonlinear Optics

G&H designs and produces nonlinear optic (NLO) crystals for nonlinear frequency conversion applications from the deep UV to the far infrared. G&H offers crystals, complete with AR coatings and packaged in housings, for wavelength conversion and polarization control over a wide spectral range. 

We offer a wide selection of materials such as beta-barium borate (BBO), cadmium Selenide (CdSe), cadmium sulfide, (CdS), potassium di-hydrogen phosphate (KDP), and potassium di-deuterium phosphate (KD*P). All are fabricated on a made-to-order basis in-house using advanced orienting, sawing, grinding, and lapping technologies. From one-off to volume OEM applications, we supply bespoke crystals for research and industry use. 

G&H produces a variety of nonlinear optical crystals for use internally for G&H products as well as for external customers.  Proprietary software routines and unique crystal growth capabilities enable us to supply customized crystals for a variety of applications. 

G&H has grown KDP boules with masses greater than 635 kg. We produce crystals with cross sections as large as 43 cm square for internal confinement fusion (ICF) applications. We also grow the largest single crystal CdS and CdSe crystals used for infrared waveplates. 

Our product managers and sales engineers routinely work with customers, applying our expertise to develop custom products to meet the demands of specific applications.  


G&H internally fabricates the crystals with advanced orienting, sawing, grinding, and lapping technologies. 


Precision polishing techniques achieve large diameter or high aspect ratio optics with excellent transmitted wavefront characteristics.


We AR coat Pockels cell crystals, windows, harmonic generating crystals, and waveplates using our vapor deposition and IBS coating systems.

We utilize vacuum deposition processes to apply metal electrodes to flat polished or fine-lapped surfaces as well as cylindrical surfaces. 

G&H has also developed proprietary solgel AR coating processes for crystals ranging in size from 5 mm to over 300 mm across.


We produce crystals with cross sections as large as 43 cm square or as small as a few millimeters. Special geometrical shapes with aspect ratios better than 100:1 include thin plates with diameters greater than 300 mm and smaller diameter plates as thin as 400 µm. Brewster-cut bars are also available for low-loss intra-cavity laser applications. 

Fixtures and housings

Mechanical stress and strain of fixtures or housings can degrade optical performance of crystal or nonlinear optics. Our line of crystal holders accommodate a wide range of crystal sizes and apertures. Designed to minimize mechanical stress and strain, our standard and custom fixtures and housings are supported by our own machine shop, providing tight tolerance and high quality manufacturing.


G&H has extensive facilities for transmission and reflection interferometry, as well as contrast ratio measurements. We can measure insertion loss, uniformity of birefringence, and other important characteristics. 


Our CdSe crystals are used in infrared waveplates and MIR harmonic generator applications. CdS crystals are also used for IR waveplates. 

BBO is typically used for Pockels cells and for harmonic generators.

LiNbO3 and TeO2 are used in acousto-optic devices such as beam deflectors, modulators, Q-switches, and pulse pickers.

KDP and KD*P are used for Pockels cells and as electro-optic Q-switches.

LiNbO3 is also used in waveguides, low pass filters, isolators, and Wollaston prisms.