SSL T&M news: Gigahertz-Optik and UV-C, Vektrex, and Gamma Scientific

With interest raging relative to the use of ultraviolet (UV) radiation to combat the coronavirus, Gigahertz-Optik has announced a new member of its portable radiometer family that can be used to assess the germicidal effectiveness of UV-C-band (100–280-nm) systems and to check UV-C systems for safety compliance. Vektrex is now offering junction temperature measurements as a test and measurement (T&M) service for new solid-state lighting (SSL) product designs. Gamma Scientific, meanwhile, has delivered a new standard light source for calibration of other light-measurement test devices.

UV-C characterization

We have regularly published articles over many years describing the disinfection capabilities of UV-C radiation, most often with a focus on water purification and sterilization. UV-C energy can also kill pathogens such as the coronavirus. Seoul Viosys, for instance, has said that a university research team found the company’s UV-C LEDs capable of sterilizing a novel coronavirus sample in 30 seconds. So it’s not surprising that UV-C is gaining much notice in the wake of the current pandemic and the application that is sometimes called UV germicidal irradiation (UVGI).

The potential of the technology led Gigahertz-Optik to deliver a new radiometer, the UV-3726, capable of verifying the potential of UV-C to kill pathogens and also capable of verifying that such systems don’t pose a danger to humans. The device is a handheld radiometer, although the photodiode-based sensor is connected via a cable so that humans testing a device aren’t exposed to UV-C radiation.

The company said the effectiveness of UV-C in killing pathogens is dependent on the dose or duration and the wavelength of the emission. The device can measure emission levels to beyond 100 mW/cm² with resolution of 0.001 µW/cm². In checking for safe levels of UV-C radiation, the instrument can monitor for levels below 0.2 µW/cm² at 254 nm where mercury lamps radiate or below 0.1 µW/cm² — both over eight hours of exposure.

Accurate LED measurements

Moving to accurate characterizations of LEDs in general, a key to such activity is accurate measurement of junction temperature. In the most recent issue of our magazine, Vektrex contributed an article that described a new JEDEC Electrical Test Method for capturing accurate junction temperature.

Vektrex manufactures and sells the instruments product developers need to make such measurements. And now the company will further offer laboratory services to measure the junction temperature in new product designs.

Calibration standards

Of course, all test and measurement devices require accurate calibration on a specific schedule so that characterization data can be trusted by product developers and ultimately a company’s customers. Gamma Scientific offers NIST (National Institute of Standards and Technology)-traceable white light sources that can be used for the calibration of spectroradiometers, radiometers, and photometers.

The new RS-12D Series supports ISO 17025 calibration. The source can be used to calibrate detector responsivity or to measure reflectance and transmittance. The 2856K-CCT source delivers wavelengths ranging from 380–1100 nm.