Optical Parametric Oscillators (OPOs)
Widely Tuneable Pulsed Lasers for the Range 205 - 3260nm
GWU Lasertechnik's family of optical parametric oscillators (OPOs) are widely tuneable pulsed lasers which are pumped by a Q-switched Nd:YAG laser at either 1064, 532 or 355nm. We offer broad-band as well as mid-band OPOs based upon crystals of BBO that tune between 410 - 2630nm, plus optional UV extension down to 205nm for the mid-band models. We also offer an infrared OPO based upon a crystal of KTP which tunes in the range 1580-3260nm. For added convenience, the OPO can be seamlessly combined into a single "Integra" housing with the pump laser. The GWU OPOs are suitable for pumping with almost any Q-switched Nd:YAG laser, including brands such as Spectron, Big Sky Laser, Quantel, Continuum, New Wave Research and Spectra Physics (Quanta Ray). For those requiring a complete system including pump laser, we are happy to recommend the SpitLight series of Nd:YAG lasers from Innolas.
The BBO OPO Family: basiScan; versaScan; & premiScan
Our BBO OPO family provides a solution for all needs and budgets, from the highly-affordable basiScan, through the modular versaScan to the high-performance premiScan. We offer two generic types of BBO OPO; the type I and type II phase-matched versions. We refer to the type I models as "broadband" in which the linewidth varies with wavelength from about 10 to 100cm-1. The type II OPOs are termed "mid-band" in which the linewidth remains constant at about 4cm-1 as the OPO tunes. The midband OPOs also offer several other advantages: the gap in the tuning range characteristic of broadband OPOs (~ 680-740nm) is absent; the OPO output can be frequency doubled or sum frequency mixed to provide access to the UV band; and the signal and idler waves from the OPO have an orthogonal polarisation, allowing the two wavelengths to be separated even at 710nm using polarisation separation optics.
GWU's OPOs stand out as having high conversion efficiencies, particularly those models with pump beam recycling and in the premiScan/MB; this model uses two BBO OPO crystals which serves to maximise the outputs at the extremes of the tuning range. All models use coated BBO rather than uncoated crystals in sealed housings to avoid unnecessary reflection losses, while a deliberately relaxed pump beam fluence promotes the industry's highest long-term reliability and dependability. On a practical note, our customers tell us that we have the most advanced and user-friendly software interface (which includes a LabView driver library). Active wavelength control of the OPO is possible using the optional wavemeter. The top-of-the-range premiScan/MB/ULD model has an enhaced resonator design which promotes a circular, low divergence beam with the highest pointing stability, attributes which make the -ULD the OPO of choice for long beam-path studies.
The midband OPOs (versaScan/MB and premiScan/MB and -ULD) can be combined with our uvScan harmonic generation unit which provides an output in the 206-412nm range. The uvScan achieves up to ~ 3% conversion of the 355nm pump energy into the second harmonic of the OPO. For the very highest UV outputs, sum frequency mixing of the OPO and residual 1064nm radiation is offered which provides up to 7% conversion and energies in excess of 40mJ.
To help you to decide on the best OPO option for your experiments, we have summarised the main features of the BBO models in the table below.
|
basiScan |
versaScan/BB |
versaScan/MB |
premiScan/BB |
premiScan/MB |
|
|
Overview |
Ultra-compact |
Modular |
Modular |
High-performance |
High-performance |
|
Special Features |
|
BB/HE > 25% higher efficiency |
|
|
Enhanced efficiency at extremes of tuning range vs. versScan/MB |
|
Type |
BBO type I |
BBO type I |
BBO type II |
BBO type I |
BBO type II |
|
Linewidth |
~10-100cm-1 |
~10-100cm-1 |
~4cm-1 |
~10-100cm-1 |
~4cm-1 |
|
Tuning |
410-2500nm |
410-2550nm |
412-2550nm |
410-2630nm |
410-2630nm |
|
Pump |
<240mJ |
<320mJ |
<320mJ |
<650mJ |
<650mJ |
|
Operation |
Manual |
Manual or motorised |
Manual or motorised |
Manual or motorised |
Manual or |
|
No. OPO |
1 |
1 |
1 |
1 |
2 |
|
Pump Beam Recycling |
No |
BB - No |
Yes |
Yes |
Yes |
|
Beam |
External dichroics - optional |
Internal |
Internal |
Internal |
Internal |
|
uvScan |
N/A |
N/A |
206-412nm |
N/A |
206-412nm |
» Click here for the basiScan brochure
» Click here for the versaScan brochure
» Click here for the versaScan/HE brochure
» Click here for the premiScan brochure
» Click here for the premiScan/ULD brochure
» Click here for the uvScan brochure
The spitScan OPO
The GWU spitScan 200 is a complete, tuneable laser system which integrates an Innolas SpitLight 200 Nd:YAG pump laser head (60mJ @ 355nm) with a basiScan BBO OPO into a single, compact housing. The advantages of the spitScan over the more usual approach of mounting the pump laser and OPO separately onto an optical table or breadboard include:
- Fully enclosed beam paths for enhanced safety and use in "hostile" environments.
- Stable alignment of pump beam into the OPO.
- More easily transported.
» Click here for the spitScan 200 brochure
The spitScan IR OPO
The spitScan 200 IR is an infrared version of the spitScan BBO. In this case, the OPO is based upon a crystal of KTP which is pumped at 1064nm by the Innolas SpitLight 200 Nd:YAG laser. The OPO output tunes from 1580 - 1950nm on the signal wave and from 2340 - 3260nm on the idler wave. Selected ranges (e.g. 2.9 - 3.0µm) can be optimsed on request.