1. What is the BT Series Laser designed for?

 

The BT Series Mini‑Benchtop Laser is designed specifically for Raman spectroscopy and analytical instrumentation, where wavelength stability and spectral purity are critical. It delivers ultra‑stable center wavelengths, narrow linewidth, and reliable output power, helping ensure consistent, repeatable Raman measurements in both research and routine laboratory workflows.

 

2. What makes the BT laser wavelength‑stable?

 

BT lasers use Coherent SureLock™ technology, stabilized by a PowerLocker® Volume Holographic Grating (VHG). This design locks the laser to a precise wavelength and maintains stability across the entire 0–100% power range, reducing drift caused by temperature or power adjustments and preserving spectral accuracy during long measurements.    Typically <0.5 wavenumber stability over long periods.

 

3. Why is wavelength stability important for Raman spectroscopy?

 

Stable wavelength ensures that Raman peak positions remain fixed over time, which is especially important for:

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• Library matching and material identification

• Long integration times

• Quantitative or comparative measurements

 

The BT laser’s locked wavelength minimizes recalibration and improves confidence in repeat measurements.

 

4. Which wavelengths are available?

 

Standard BT Series wavelengths include:

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• 638 nm

• 785 nm

• 830 nm

• 1064 nm

 

Custom wavelength options may also be available upon request, depending on application needs.

 

5. How do I choose the right wavelength?

 

For casual Raman users:

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• 785 nm – Most common choice; good balance of signal strength and fluorescence reduction

• 830 nm / 1064 nm – Better for highly fluorescent samples

• 638 nm – Higher Raman scattering efficiency but more sensitive to fluorescence

 

Your choice typically depends on sample composition and detector sensitivity.

 

6. What output power levels are supported?

 

The BT Series provides continuously adjustable output power, from a few milliwatts up to 500 mW (model‑dependent). This flexibility allows users to optimize signal strength while managing sample heating or photodamage.

 

7. How stable is the output power?

 

Typical long‑term power stability is better than 1–3%, supporting consistent Raman signal levels during extended experiments or repeated measurements.

 

8. How narrow is the spectral bandwidth?

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The BT laser offers a typical spectral bandwidth of ~0.08 nm (FWHM), enabling:

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• High spectral resolution

• Improved Raman peak separation

• Cleaner spectra with reduced background noise

 

This is particularly helpful for materials with closely spaced Raman features.

 

9. Is the BT laser easy to use in a laboratory setting?

 

Yes. The BT Series is designed for plug‑and‑play laboratory use, featuring:

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• Touchscreen user interface

• Simple front‑panel power adjustment

• Integrated safety features (keyswitch, E‑stop, emission delay)

• Internal drive electronics and temperature control

 

No external laser controller is required.

 

10. How quickly does the laser warm up?

 

The laser reaches operating stability in under one minute, allowing fast startup and minimal wait time before measurements. For optimal performance, a few additional minutes can be allowed in highly sensitive applications.

 

11. What kind of fiber output does it use?

 

The BT Series comes standard with:

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• 105 µm core

• 0.22 NA multimode fiber

• FC/PC connector

 

Optional patch cables are available with FC/PC or SMA connectors. Other fiber configurations may be available upon request.

 

12. Why is fiber cleanliness important?

 

Clean fiber connections are critical for:

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• Maintaining output power and spectral quality

• Preventing connector damage

• Avoiding permanent fiber or laser damage at higher powers

 

Routine inspection and cleaning are strongly recommended before use.   Damaged connectors due to cleanliness are not covered by warranty.

 

13. What operating environment is required?

 

The BT laser is intended for standard laboratory environments:

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• Operating temperature: 0 °C to 40 °C

• Non‑condensing conditions

• Reasonable airflow for thermal dissipation

 

No special cooling or environmental enclosure is required.

 

14. What safety features are included?

 

Integrated safety features include:

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• Laser enable keyswitch

• Emergency stop (E‑stop)

• 20‑second emission delay

• Remote interlock connections (lab door or enclosure)

 

These features support compliance with Class 3B laser safety practices when properly implemented

 

15. What remote connectivity options are available?

 

The BT Series supports:

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• Remote interlock connections (via rear terminal block)

• USB‑to‑serial communication for basic remote control and monitoring

 

This enables integration with lab automation or external control systems while retaining local front‑panel operation.

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16. What is the difference between vacuum and air-referenced wavelengths?

 

Because we tightly control wavelength accuracy and tolerance, it is important to specify the reference medium used for wavelength measurement.

 

Light travels slightly more slowly in air than in vacuum, causing the wavelength in air to be marginally shorter. To avoid ambiguity and ensure consistency, wavelengths in our datasheets are vacuum‑referenced, which is also the convention used by many spectroscopy databases.  As an example, a HeNe laser specified at 632.991 nm in vacuum corresponds to 632.816 nm in air. This difference does not indicate a physical change in the laser, only a difference in how the wavelength is referenced.