Light Sources
£350.00
ISO 10677: 2011 – Ultraviolet light source for testing semiconducting photocatalytic materials.
- Description
Description
All the ISO tests utilised make reference to the use of a suitable UV light source. However, typically three different types are recommended – two types of BLB and a xenon arc lamp. The relative light intensity vs. wavelength profiles for (a – solid) a xenon arc lamp, (b – dashed) a BLB light source with λmax (other than peak at 365 nm) at ca. 351 nm and (c – bold) a BLB light source with λmax (other than peak at 365 nm) at ca. 368 nm are illustrated below.
The specification of a suitable UV light source is paramount to repeatability and reproducibility of the standard tests reported, and since the photocatalytic efficiency of a system depends upon the spectral distribution and radiant intensity of the light source, only one type of BLB, namely one with a europium-doped fluoroborate phosphor is used in our testing. In order to evaluate photocatalytic materials for use in sunlight however, xenon arc lamps are used.
At QIPS we can measure the emission spectrum and UV irradiance (units: mW/cm2) of your submitted light source using a calibrated spectroradiometer, and compare and contrast it to that of other light sources.
Further Information
Black light fluorescent lamps are made as normal white light fluorescent tubes except that only one phosphor is used, and the glass envelope has a blue filter which ensures that most of the light emitted is UVA light. The two types of BLB arise because there are two types of phosphor, namely: (i) europium doped fluoroborate, which produces a UV emission peak ranging from 368-371 nm and a band width of 20 nm and (ii) lead-doped barium silicate with a UV emission peak ranging from 350-353 nm and a band width of 40 nm [1].
To produce solar simulated UV light (and ensure the significant visible component is removed) we use a UG5 filter (cuts out most light between 400-650 nm [2]) in combination with a WG320 filter (cuts out light below 300 nm [3]). The overall emission has been shown to be a very good fit to the actual solar UV emission spectrum. The removal of most of the visible light produced by the Xe arc lamp is also a very important feature, since the standards are designed for UV absorbing systems only.
We use a calibrated spectroradiometer, for measuring the UV irradiance.
The relative light intensity vs. wavelength profiles for (a – solid) a xenon arc lamp, (b – dashed) a BLB light source with λmax (other than peak at 365 nm) at ca. 351 nm and (c – bold) a BLB light source with λmax (other than peak at 365 nm) at ca. 368 nm are illustrated below.
References
[22] http://en.wikipedia.org/wiki/Black_light; accessed 01/05/2012.
[23] http://www.optical-filters.com/ug5.html; accessed 01/05/2012.
[24] http://www.heliosoptical.net/html/schott_wg_320__colorless_uv_fi.html; accessed 01/05/2012.