In the field of optical materials, fused quartz glass is highly valued for its exceptional purity, chemical stability, and wide spectral transmission range. Within the Chinese optical glass classification system, quartz glass is commonly divided into three major categories: JGS1, JGS2, and JGS3.
These designations reflect differences in ultraviolet (UV) transmission, optical uniformity, bubble/striae content, and optimal application scenarios.

1. What Does “JGS” Mean?

The acronym JGS stands for Jing Guang Shi , meaning “optical-grade quartz glass” in Chinese. The numbers 1, 2, and 3 indicate the specific optical transmission grade and intended application range.

2. Classification and Core Properties

 

Type	Spectral Range	Key Features	Typical Applications
JGS1	185–2500 nm	- Ultra-high purity, no bubbles, no visible striae - Exceptional deep UV transmission - Minimal metallic impurities	DUV lithography, excimer laser windows, UV spectrometer optics, detector windows
JGS2	220–2500 nm	- Slightly reduced UV transmission compared to JGS1 - Good optical uniformity and manufacturability	UV optical instruments, lenses, prisms, IR windows
JGS3	260–3500 nm	- Optimized for visible to IR transmission - UV cut-off around 260–270 nm - Suitable for large-size production, lower cost	Laser optics (Nd:YAG), IR optical windows, astronomical lenses, thermal imaging protection windows

 

3. Transmission Curve Analysis

The main differentiator between JGS1, JGS2, and JGS3 is their UV cut-off wavelength and spectral transmission profile.
Below is a transmission comparison chart illustrating how each type performs across the UV–Visible–IR spectrum:

Key Observations:

JGS1 Quartz wafer: Maintains >93% transmission from 185 nm, making it the top choice for deep ultraviolet (DUV) applications.
JGS2 Quartz wafer: Begins high transmission from 220 nm, suitable for standard UV–Visible applications where deep UV is not required.
JGS3 Quartz wafer: Designed for visible to infrared performance; UV cut-off around 260 nm.


 

4. Application Scenarios

4.1 JGS1 Quartz — Deep UV Specialist

Semiconductor Lithography (DUV): Photomask substrates for 193 nm / 248 nm lithography systems.
UV Laser Optics: Excimer laser windows and focusing lenses.
Analytical Instruments: UV spectrophotometer cuvettes and detector windows.

4.2 JGS2 Quartz — General UV–Visible Optics

Optical Lenses and Prisms: For precision optical instruments operating in the 220–2500 nm range.
UV Curing and Analysis: Windows for UV curing machines, medical and industrial UV analyzers.

4.3 JGS3 Quartz— Visible–IR Optimized

High-Power Laser Systems: Nd:YAG laser components where UV transmission is not critical.
Infrared Windows: For thermal imaging cameras, IR spectroscopy, and protective windows in harsh environments.
Astronomical Optics: Large-diameter lenses for telescopes and observatories.

5. Selecting the Right Grade

Choosing between JGS1, JGS2, and JGS3 should be based on:
Required Spectral Range — especially UV cut-off wavelength.
Environmental Conditions — e.g., exposure to high-energy UV, high temperatures, or corrosive chemicals.
Budget & Manufacturing Constraints — JGS1 is the highest cost due to its purity and processing difficulty; JGS3 offers better scalability and lower cost.

6. Conclusion

JGS1, JGS2, and JGS3 are not just different “grades” of quartz glass; they are engineered to excel in distinct spectral domains.
From semiconductor lithography to infrared astronomy, the correct choice of quartz glass type can directly affect optical system performance, reliability, and lifespan.
When your application involves deep UV precision optics,JGS1 Quartz wafer is irreplaceable. For broader UV–Visible work, JGS2 Quartz wafer offers a strong balance between performance and cost. And when your focus is purely in the Visible–IR range, JGS3 delivers optimal efficiency and scalability.