A spectroradiometer is a device that can measure optical emissions of a light source in terms of spectrum and optical power. It provides information such as how energy and power is distributed within the spectrum of a source.

The SpectroRaph is Hexago's spectroradiometer, but since we invented a novel way of measuring spectral emissions, we decided to give it it's own name. The core difference is that it doesn't require calibration lamps to function and has internal calibration mechanism to provide the highest quality and accuracy of spectral data.

Hexago's spectroradiometer, the SpectroRaph, allows the fast and streamlined measurement of optical emissions for both LED/lamp and laser systems, specifically in the scopes of IEC 62471 Photobiological safety of LED/lamp products and IEC 60825 Safety of Laser Products.

• Yes, the SpectroRaph is designed to fulfill the role of both a laser and LED/lamp measurement system. It can provide metrics such as power [W], energy [J], irradiance [W/m2], radiance [W/m2/sr], spectrum [AU/nm], spectral power [W/nm], spectral irradiance [W/m2/nm], spectral radiance [W/m2/sr/nm] as defined in the IEC standards.

• The SpectroRaph is specifically designed to complete measurements as defined in the IEC 60825 laser and the IEC 62471 LED/lamp system optical safety standards.

• The SpectroRaph is the only IEC validated measurement system that can measure both laser and LED/lamp systems as per IEC 60825 and IEC 62471.

• Before the SpectroRaph, only the double monochromator was validated to measure LED/lamp systems and only cosine corrected laser sensors, such as integrating spheres, were validated to measure lasers.

• The first role of the SpectroRaph is to measure laser devices and systems as per the IEC 60825 safety of laser products standard.

• The second role of the SpectroRaph is to measure LED/lamp devices and systems as per the IEC 62471 Photobiological safety of lamps and lamp systems standard.

• The SpectroRaph can also be used in general optical measurement of laser and LED/lamp systems.

• Firstly, the SpectroRaph possesses the necessary hardware to conduct power measurements under the laser standard, or IEC 60825. It also meets the standard’s equipment requirements.

• Secondly, the SpectroRaph possesses the necessary hardware to conduct spectral measurements under the LED/lamp standard, or IEC 62471. It also meets the standard’s equipment requirements.

• Thirdly, the SpectroRaph was part of a long process within the IEC committee to be admitted for LED measurements. The SpectroRaph, which is a special spectroradiometer which doesn’t require calibration lamps, was proposed as a novel method for absolute spectral measurements to the IEC convenor and committee under the TC76 process.

• We partnered with UL for the submission as they are a certification body for the IEC standard and are also part of the committee. After review, the verdict was to permit our system to evaluate the optical safety under IEC 62471, which now includes our system in the allowed equipment list of certification laboratories in the scope of IEC 62471. In short, the SpectroRaph was the first accepted spectroradiometer for the certification of LED/lamp systems and is the only tool necessary to pursue a CTF3 lab status, or the lab status required to emit certification reports as a certification lab.

• Hexago offers 3 options that cover the most relevant laser and LED wavelength ranges.

  • Visible-NIR option: Covers 330 nm to 1100 nm wavelength range

  • NIR-Mid IR option: Covers 900-1650 nm wavelength range

  • UV-Visible option: Covers 200-780nm wavelength range

• For laser power measurements, a single point measurement can take a fraction of a second, up to 1000 measurements per second or 1000 Hz [Hertz], or 1 ms [milli-second].

• For a relative spectral measurement, a single point measurement can be less than 1 ms [milli-second]. Typical LED/laser spectra can be acquired in 5 ms [milli-seconds] .

• For an absolute spectral measurement, such as spectral power [W/nm], irradiance [W/m2/nm] or radiance [W/m2/sr/nm], a single point measurement can be less than 1 s [second].

• For a pulsed source measurement, the SpectroRaph can be set to integrating mode to capture the averaged power over an arbitrary duration, say 1 s [second].

• Like any signal measurement, the measurement time depends on the signal strength or intensity. For small signals, a measurement may take more time to integrate.

• Yes, whether it is for a laser, lamp or LED systems, our spectroradiometer can handle pulsed and continuous wave sources.

• We also offer a timing option that can measure the timing of pulses up to 5 GHz [Giga-Hertz] using a high speed oscilloscope and probe for pulses down to 0.2 ns [nano-seconds].

• Depending on the pulse energy, the SpectroRaph can measure pulses from the pJ [pico-Joules] range, up to 9 𝜇J [micro-Joules] per pulse.

• Beyond the measurement of the SpectroRaph, our analysis software SafeLED intuitively handles pulse train calculations, reporting and even simulation.

• The SpectroRaph software has tracking tools for power in the case of lasers, and blue-light, burn and actinic hazards, and spectral power in the case of LED/lamp systems.

• The tracking tools allow to easily maximize the measured emissions to properly assess the risks of laser and LED/lamp systems at their worst-case scenarios.

• A measurement can be quickly done at the maximum risk positions by manually finding the peak emissions or alternatively, by using our signal optimizer tool for our automated metrology option, designed to quickly converge to the maximum emission positions.

• The SpectroRaph has swappable field-of-view limiting apertures to switch between laser and LED measurement conditions.

• Our quick connect tips and probe ends allows the measurement of laser and LED systems at the following test condition distances:

  • 0 mm (Laser)

  • 70 mm (Laser - Optional)

  • 100 mm (Laser)

  • 2000 mm (Laser)

  • 200 mm (LED)

    • All risk group field-of-views are covered

• The SpectroRaph needs to be calibrated yearly if maintained within the environmental specifications. Out of specification environmental conditions may affect the validity of a calibration.

• The SpectroRaph requires a yearly calibration of its measuring elements. Each optical component can be sent back to their respective manufacturer using their calibration forms, or sent back to us to handle that for you.

• The SpectroRaph does not need any calibration light source, such as calibrated lamps, atomic line lamps or anything of the sort.

• The SpectroRaph comes in different levels of automation.

  • Motorized Probe only: Get the probe that you can attach to your own automation setup and use with our software for acquisitions or our API.

  • Motorized Probe + Fast Stages: Control Pitch, Tilt, X,Y and Z axes of motorized motion. Perfect for repeatable and fast measurements.

  • Motorized Probe + Robot Arm: Control a 6-axis robotic arm for the greatest amount of versatility. Perfect for testing products of any shape or kind.

• The SpectroRaph possesses different safety features to protect itself from collisions. These may include retractable and spring-loaded probe tips, replaceable probe tips, magnetic attachment bases, over-current detection and more. This is to ensure that a wrong move won’t damage your products or the probe, or most importantly, your engineers.

• The process to become an accredited laboratory is fairly complex and has wide requirements. While our equipment complies with the equipment requirements to become an accredited laboratory for both LED and lasers, further steps need to be taken in order to comply with IEC regulations. These steps include and are not limited to:

  • Calibration and tracking requirements

  • Traceability requirements

  • Undergoing Customer Testing Facilities [CTF] certifications

    • CTF1 certification and witness testing

    • CTF2 certification and witness testing

    • CTF3 certification and witness testing

  • Yearly certification body audits

  • Personnel training and training tracking

• In the case becoming a CTF3 LED and/or laser laboratory is in your mind, you can find the National Certification Body list here and get started in your certification process with them if you have one of our SpectroRaphs in your lab.

• If you are a National Certification Body, let us know if you would like to know more about our methodology and measurement systems.