This page covers flat quartz selected by its spectral transmission grade — the driver is JGS1/JGS2/JGS3 (or equivalent) selection matched to your wavelength range, layered onto plate or window dimensions from the other flat-quartz pages.
Material Grade & Transmission
| Grade | OH Content | Transmission Range | Best For |
|---|---|---|---|
| JGS1 | ~2000 ppm | 185 – 2500 nm; >90% at 185nm | Deep-UV optics, excimer laser components, semiconductor equipment windows |
| JGS2 | Moderate | ~220 – 2500 nm; Tavg >85% | General-purpose UV-visible optics, sight glasses, UV lamp envelopes |
| JGS3 | Low | 185/260 – 3500 nm; Tavg >85% | Broadband including IR, high-temperature/high-power laser use |
International equivalents: JGS1 ≈ Heraeus Suprasil 1/2; JGS3 ≈ Heraeus Suprasil 300.
Standard Sizes
| Example | Specification |
|---|---|
| Small optical window | 25 × 25 mm, thickness 0.5 – 1 mm (cited examples for JGS2/JGS3) |
| General optical plate | Custom size to drawing |
| Max working temperature (JGS3 example) | 1250°C |
Surface Quality
| Parameter | Specification |
|---|---|
| Surface roughness | Ra <1 nm typical polished optical grade |
| Scratch-dig | 40/20 (per MIL-O-13830), or tighter on request |
| Impurity content | 40–50 ppm (cited JGS2/JGS3 example spec) |
| Transmission (spectral) | >85% average across the grade’s stated range |
Application
UV-Vis absorption spectroscopy, spectro-electrochemical cells, semiconductor equipment windows, general optical instrumentation.
FAQ
Which grade should I choose?
JGS1 for deep-UV work below ~220nm. JGS2 for general-purpose UV-visible optics at lower cost. JGS3 for infrared transmission and high-power laser or high-temperature applications.
What surface quality should I specify?
40/20 scratch-dig is a common baseline for demanding optical use; tighter grades are available where stray light or scatter is critical — confirm against your optical system’s tolerance.