Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Transfer spectrophotometer
A Perkin-Elmer Lambda 1050 spectrophotometer is used to complement the reference reflectance and transmittance 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.
Specifications/Capabilities
Conditions for transmittance and reflectance measurements using the Perkin-Elmer Lambda 1050
| Transmittance | Reflectance | |||
|---|---|---|---|---|
| Regular | Diffuse | |||
| Geometrical | ||||
| Illumination Angle | 0° | 0° | 3.3° (specular included) | 0° (specular excluded) |
| Viewing Angle | 0° | 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 |
| Spectral | ||||
| 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 |
| Measurand | ||||
| 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% | 0.4% to 1% | 0.4% to 1% |