MDR-41 Monochromator

MDR-41 monochromator is intended to be used as a monochromatic light source in a wide spectral range.

The instrument is built according to a proprietory optical arrangement using off-axis parabolic lens, which allows a considerable improvement of resolution, and reduction of stray light level in contrast to the conventional Fastie configuration.

To illuminate the entrance slit of the instrument, a mirror condenser is used which contains an optical filter unit to remove the higher diffraction orders.

Specifications

Parameter Specification
Wavelength range, nm 200 – 25000
Aperture ratio 1 : 6
Focal distance of the mirror lens, mm 300
Inverse linear dispersion *, nm/mm 2.0
Spectral resolution *, nm (at I=546.07nm, slit width 5 nm, slit height 2mm), better than 0.02
Stray light level at 8 times slit bandpass from He-Ne laser line of 632.8 nm * 10-5
Wavelength reproducibility, nm 0.025
Wavelength accuracy *, not worse than 0.2
Monochromator dimensions, mm 250x440x280
Monochromator mass, kg 12

*Specified for the 1500 grooves/mm grating.

Dedicated spectrometric installations

Basing on MDR-41 monochromator, “OKB SPECTR” develops and manufactures dedicated spectrometric installations for recording spectral characteristics of light sources and photodetectors, measuring spectra of transmission, specular and diffuse reflectance, for excitation and registering luminescence spectra. Liquid and solid samples can be studied with various illumination geometry.

The spectrometric installations are built according to the Customer’s design criteria basing upon MDR-41 monochromator or others. The installation operation is governed by a microprocessor controller consisting of a base unit with the processor card, and step motor control card. Using additional modules, the controller provides operation of the photomultiplier tube (PMT), photodiode, photoresistor with thermoelectric cooling, CCD array, performs signal detection in the modes of DC amplifier, photon counting and synchronous detection. The controller is configured in accordance with the Customer’s choice.

Спектрометр для регистрации спектров рассеивания и флуоресценции поверхностей твердых образцовDepending on the required wavelength range and type of application, the installations are equipped with light sources (lamp, laser, globar) and detectors (PMT, photodiode, thermoelectrically cooled photoresistor, pyroelectric detector), appropriate projecting optical system, sample holders of required configuration with necessary adjustment movement mechanisms, temperature lamp for energy calibration, devices for video monitoring of the sample area under study using a common eye lens or video camera, etc.

The installations are mounted on a single optical bench; laboratory furniture and accessories can also be supplied. Signal detection is accomplished in the modes of DC amplifier, photon counting and synchronous detection. The installation control and data processing is carried out by an external personal computer.

Main components of the MDR-41 monochromator based spectrometric installation

Description Comments Illustration
MDR-41 Monochromator High specification monochromator – the core of the spectrometric installation MDR-41 Monochromator
Mirror condenser In standard delivery set, projects with magnification the light source image onto the monochromator entrance slit Зеркальный конденсор
Gratings and light filters for removal of the higher diffraction orders The gratings are changed manually; the light filters can be changed either manually or automatically. Дифракционные решетки и светофильтры
  3000 grooves/mm (200-500 nm)
  1500 grooves/mm (400-1000 nm)
  750 grooves/mm (800-2000 nm)
  600 grooves/mm (200-500 nm)
  300 grooves/mm (200-500 nm)
  150 grooves/mm (200-500 nm)
  75 grooves/mm (200-500 nm)
  37,5 grooves/mm (200-500 nm)
Optical bench The primary component for the spectrometric installation mounting. Optical bench
Detection unit for 200-800nm wavelength range (FEU-100 photomultiplier tube based)) The unit is mounted on the optical bench, and fixed to the monochromator exit slit flange. Detection unit
Detection unit for 800-1200nm wavelength range (FEU-62 photomultiplier tube based)
Detection unit for 1100-2500nm wavelength range (thermoelectrically cooled photoresistor based) The unit is fixed to the monochromator exit slit flange. Detection unit
Detection unit for 1100-25000nm wavelength range (pyroelectric detector based) The unit is mounted on the optical bench, and fixed to the monochromator exit slit flange. Detection unit
Deiterium lamp based light source with power supply. For 200-400nm wavelength range. The light sources are mounted onto the optical bench. Each type of light source comprises features optimal for specific study applications. The light sources
Hg-He lamp based light source with power supply. For wavelength scale calibration.
Halogen lamp based light source with power supply (lamp power is subject to determination). For 1000-25000nm wavelength range.
IR radiating element based light source with power supply. For 1000-25000nm wavelength range.
Xenon lamp based light source with power supply. For 200-4000nm wavelength range. Features an intensive UV radiation, and visual light similar to sunlight. The light sources
Temperature lamp based light source with power supply. Has a particular spectral distribution with strictly specified energy parameters. The light sources
Sample compartment One design version of sample compartment and sample holder. Sample compartment and sample holder
Sample holder
Microprocessor unit with software package for communication with the computer, monochromator control, photodetector data acquisition and processing, and photodetector power supply The microprocessor unit provides electronic control of the spectrometric installation, and two-way computer interface. Microprocessor unit