Reference Transmittance Spectrophotometer (RTS)

Description:

The Reference Transmittance Spectrophotometer (RTS) is the national reference instrument for regular spectral transmittance measurements of non-fluorescent samples at room temperature.

The illuminator has two sources, a deuterium (D₂) arc lamp and a quartz-tungsten-halogen (QTH) incandescent lamp, a spherical mirror, a chopper, a prism-grating monochromator, a parabolic mirror, a polarizer, and an iris. A sample carriage moves the sample in and out of the influx beam. The receiver has a block for the efflux beam, a spherical mirror, and integrating sphere, and a detector, either a photomultiplier tube (PMT) or a silicon (Si) or extended indium-gallium-arsenic (InGaAs) photodiode.

Specifications / Capabilities:

Conditions for transmittance measurements using RTS.

	Geometrical
	Illumination Angle	0°
	Viewing Angle	0°
	Sampling Aperture	4 mm to 20 mm

	Spectral
	Wavelength	250 nm to 2500 nm
	Bandwidth	1.5 nm or 3 nm
	Polarization	0° to 90°

	Sample Size	10 mm to 50 mm

	Measurand
	Quantity	Transmittance T
	Technique	Absolute
	Range	0.001 to 1
	Uncertainty (k=2)	0.1% to 0.5%

Associated Programs/Projects:

Spectrophotometry
Spectral tri-function automated reference reflectometer (STARR)
Transfer spectrophotometer

Reference transmittance spectrophotometer

Contact

Name: Catherine Cooksey
Phone: 301-975-6208
Fax: 301-975-6991
Email: ccooksey@nist.gov
Address:
100 Bureau Drive, M/S 8443
Gaithersburg, MD 20899-8443