ABSTRACT
We report the design and construction of a cell that enables precisely controlled measurement of UV∕Vis spectra of thin films on transparent substrates at temperatures up to 800 K. The dimensions of the setup are accommodated by a standard Varian Cary 5E spectrophotometer allowing for widespread use in standard laboratory settings. The cell also fits in a Bio-Rad IR-spectrometer. The cell is constructed with an outer water cooled heat shield of aluminum and an inner sample holder with heating element, thermo-resistor and windows, made from nickel coated copper. The cell can operate both in air, and with an inert gas filling. We illustrate the utility of the cell by characterization of three commercially available near infrared absorbers that are commonly used for laser welding of plastics and are known to possess high thermal stability.
ABSTRACT
The emission spectrum of mercury has a notable line at about 365 nm under both low and medium-high pressure conditions. A simple filter based on a solution of dysprosium ions, Dy(3+), is shown to be very useful for applications of Hg-light sources where this line is unwanted. The presented filter is cheap, robust, and stable towards degradation or bleaching - even under intense irradiation. The absorption spectrum for the Dy-filter is presented along with emission spectra from both low-pressure and high-pressure Hg-lamps to illustrate the utility of the technique under best-case and worst-case conditions. Attenuation of the 365 nm spectral line is almost total for the low-pressure source whereas for the high-pressure source the attenuation is about a factor of three.
