MIDL: Wavelength Calibration
Lamp
The MIDL is an eye-safe calibration
lamp that can be used with all
spectrometers, spectral imaging and
hyperspectral microscopy systems
Wavelength Calibration For Spectral
Microscopy Instruments
Wavelength calibration of spectral and hyperspectral
systems should have taken place in the factory.
However, after transportation, installation and time,
wavelength accuracy can change.
From a day to day standpoint there will rarely be
noticeable differences, however when data is
compared with that acquired in other labs, on the
same or different instruments, there may be
significant discrepancies.
For those researchers building their own systems
the question of wavelength accuracy has to be
settled before work can start.
The MIDL lamp provides an eye-safe solution that
comes in two formats; pencil and flat. Use the pencil
lamp for upright and the flat version for inverted
microscopes. The pencil lamp is shown in Figure 1.
The MIDL, wavelength calibration Multi-Ion
Discharge, Lamp
The MIDL emits Hg+, Ar+ and inorganic
fluorescence emission lines to provide an eye-safe
absolute rather than a relative, wavelength line
spectrum.
Bright emission lines occur 365, 405, 436, 546, 611,
695, 811 and 912-nm- among others! This enables
effective wavelength accuracy validation over the
same wavelength range.
See Figure 2.
Use the MIDL wavelength calibration lamp with:
Any spectral or hyperspectral imaging system.
Spectrometers and imaging spectrometers
Microscope mounted multispectral imaging systems
based on AOTF, LCTF devices and interferometers
Note: Ar+ emission wavelengths fade rapidly above
650 nm. Requires a fast wavelength scan or a
spectrograph that will acquire all wavelengths
simultaneously
See also the NIST certified radiometric light source
Figure 1: The MIDL hyperspectral
microscopy wavelength calibration
“pen Light” can be placed at the
focus of a microscope objective
Figure 2: The MIDL lamp spectrum for
wavelength calibration of hyperspectral
microscopy instruments