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Transfer spectrophotometer

A Perkin-Elmer Lambda 1050 spectrophotometer is used to complement the reference instruments. It performs this function by measuring samples relative to standards calibrated on the reference instruments. The instrument measures non-fluorescent samples at room temperature. The conditions of measurement and measured quantities for this instrument are given below. The illuminator has two sources, a deuterium (D2) arc lamp and a quartz-tungsten-halogen incandescent lamp, order-sorting filters, a double-grating monochromator, and a chopper. The sample compartment has two beams, one for the reference and one for the sample. Integrating sphere accessories are added for diffuse reflectance and transmittance measurements. The receiver has collection optics and photomultiplier tube (PMT), indium-gallium-arsenide (InGaAs), and lead sulfide (PbS) detectors.


Conditions for transmittance and reflectance measurements using the Perkin-Elmer Lambda 1050

  Transmittance Reflectance
  Regular Diffuse    
Illumination Angle 3.3° (specular included) 0° (specular excluded)
Viewing Angle Hemisphere Hemisphere Hemisphere
Sampling Aperture 13 mm by 5 mm 22 mm by 10 mm 15 mm by 4 mm 15 mm by 4 mm
Wavelength 250 nm to 2500 nm
Bandwidth 0.5 nm to 20 nm
Polarization Slight
Sample Size 10 mm to 50 mm cuvette 25 mm to 50 mm 25 mm to 100 mm 25 mm to 100 mm
Quantity Transmittance Transmittance Reflectance Factor Reflectance Factor
Technique Absolute Absolute Relative to PTFE Relative to PTFE
Range 0.001 to 1 0.001 to 1 0.001 to 1 0.001 to 1
Uncertainty (k=2) 0.2% to 0.5% 0.2% to 0.5% 0.2% to 1% 0.2% to 1%


Created November 16, 2009, Updated November 15, 2019