UV lasers for metrology: replace your argon-ion source

Build the source specification around your measurement. Our 349 and 360 nm single-frequency CW lasers are the starting choices for coherent UV setups; our 364 nm CW source serves measurements led by intensity and spatial beam quality. We can help match wavelength, power, delivery and control to the instrument.

Published source specifications: [2][3][6]. Confirm the ordered configuration, delivered power and the stability and calibration needed for your uncertainty budget.

UV argon configurations include lines near 351.1 and 363.8 nm. Record the line and delivered power actually used by the instrument. If it accepts a wavelength change, our 349 and 360 nm single-frequency sources offer routes to a modern CW UV design. Preserve an exact-line requirement when the sample, optics or measurement method demands it. [1][2][6]

Choose the source around phase stability, calibrated wavelength, coating transmission, sample response and detector performance. A functional replacement is accepted by demonstrating the required measurement performance at the new wavelength.

For a length measurement, the wavelength sets the scale. A narrow line supports coherence, while calibrated operating wavelength and frequency stability control different parts of the error budget. A nominal wavelength tolerance is not a statement of interferometric accuracy. In air, include refractive-index compensation appropriate to the UV wavelength. [7][8][9]

Our UV-FN-349-SLM specification, for example, separately lists 349 ±1 nm centre wavelength and <1 MHz linewidth. Use the centre-wavelength tolerance to set the permitted operating wavelength, and the linewidth to define the spectral requirement. Confirm the ordered configuration. [2]

1. 01

   Baseline the old instrument

   Record the exact line or line set, power at the instrument and sample, beam profile, noise, calibration and a representative measurement.

2. 02

   Set the wavelength requirement

   State centre wavelength and tolerance, the permitted method change, drift and whether wavelength tuning or locking is required.

3. 03

   Set temporal and spectral limits

   Define CW or pulse format, linewidth, side-mode rejection, intensity-noise bandwidth and stability over a complete run.

4. 04

   Verify optical and control interfaces

   Check beam height, waist location, polarization, coupling losses, modulation, shutter, monitoring, interlock and emergency-stop interfaces.

5. 05

   Repeat the measurement on references

   Recalibrate with the new source, use matched sample conditions and compare signal, background, repeatability and relevant sample changes.

6. 06

   Document the accepted configuration

   Retain the actual measured wavelength, delivered power, software settings, revised optical parts and the agreed pass criteria. Qualify the complete instrument.

Both wavelength figures are original plots of cited numerical facts, drawn with standard plotting software. No third-party photograph, manufacturer drawing or research figure is reproduced. The linked documents retain their respective copyright and licence terms. Download the figure provenance record ↗

1. [1]McClelland, J. et al., Journal of Research of NIST 108, 99–113 (2003). Accuracy of Nanoscale Pitch Standards Fabricated by Laser-Focused Atomic Deposition. Primary UV metrology research: Section 3 reports argon-ion output spanning 333.6–363.8 nm and diffraction measurements using the 351.1 nm line.
2. [2]Precisometer specification library. UV-FN-xxx-SLM series specification. 349 ±1 nm, 50–100 mW CW and <1 MHz linewidth. The row heading says nm but its value explicitly uses MHz; confirm the agreed specification.
3. [3]Precisometer specification library. UV-FN series: 364 nm specification. 364 ±1 nm, CW, 1–100 mW and TEM00. No linewidth or SLM specification is given in this sheet.
4. [4]Precisometer specification library. UV-FN-xxx-LN series: 364 nm specification. The wavelength row states 363.8 ±4 nm. The low-noise label does not establish exact-line matching or single-frequency operation.
5. [5]Wei, Z. et al., Optics & Laser Technology 185, 112611 (2025). Single-frequency continuous-wave solid-state 363.8-nm ultraviolet source generation by frequency tripling of a 1091-nm fiber laser. Research demonstration of a >20 mW single-frequency CW source at 363.8 nm; not a claim of a catalogue product or a guaranteed retrofit.
6. [6]Precisometer specification library. UV-FN-xxx-X series specification. 360 ±1 nm, 1–50 mW CW and <1 MHz linewidth for the 360 nm column.
7. [7]NIST. Wavelength References for Interferometry. Wavelength uncertainty, positioning accuracy and the effect of air refractivity. General metrology principles; no UV source certification is implied.
8. [8]Stone, J., Phillips, S. D. and Mandolfo, G. A., Journal of Research of NIST 101, 671–674 (1996). Corrections for Wavelength Variations in Precision Interferometric Displacement Measurements. Primary derivation of the reflection-interferometer phase relationship and wavelength corrections. The guide writes the wavelength in terms of vacuum wavelength and refractive index.
9. [9]Pedulla, J., Deslattes, R. and Lawall, J., NIST (2000). A Frequency Stabilized Laser Array for Use in Displacement Metrology. Primary metrology research illustrating why short-term spectral behaviour and long-term frequency stability are separate requirements.