In recent years the need to measure the circularly polarized luminescence (CPL) phenomenon as accurately as possible has increased by leaps and bounds. In the development of special areas such as the backlighting of liquid crystal displays, 3D and holographic displays, light sources that regulate plant growth, optical communication and printing security systems, etc. materials that exhibit circularly polarized luminescence activity play an extremely important role. After the excitation of the chiral sample with non-polarized light, the intensity difference between the emitted circularly left and right polarized light is measured. It is a measurement difficulty that a very small difference between low-intensity signals must be detected, which simultaneously requires high sensitivity, high resolution and an optical system free of disturbing signals.
The Japanese JASCO company has combined its experience in the production of circular dichroism spectrometers, fluorimeters and photometers in the CPL-300 instrument. The CPL-300 spectrometer uses a high-power xenon lamp for excitation, from which the irradiated light of the selected wavelength reaches the sample compartment through the double-prism monochromator and depolarizer. The light emitted by an excited chiral sample irradiated with monochromatic, non-polarized light enters the analyzer area with a layout of 180o, where it passes through the photoelastic modulator (PEM crystal), the polarizer unit and the double-prism monochromator to reach the photomultiplier detector (PMT). The Spectra Manager software calculates the luminescence asymmetry factor (glum) from the simultaneously collected CPL signal and the fluorescence intensity values.
Due to the layout of 180o, the CPL-300 is not only suitable for measuring liquids, but also for measuring films or powders mixed into a KBr pellet. The large sample compartment allows the use of thermostated cuvette holders, and permanent magnets with a magnetic field of 1.6 Tesla (16 kG) are available for magnetic tests. The layout of the spectrometer allows the optional introduction of external excitation light into the sample compartment, so that a measurement with an arrangement of 90o can also be performed.
Specifications:
- light source: 150 W Xe lamp
- wavelength range: 250 – 850 nm, optional 400 – 1100 nm
- spectrum recording modes: “continuous scan”, “step scan”, “auto scan”
- wavelength resolution: 0.025 nm
- wavelength accuracy:
- ±0.2 nm between 250 and 500 nm;
- ±0.5 nm between 500 and 800 nm;
- ±1.5 nm between 800 and 1100 nm
- slit width: adjustable between 1 and 4000 μm
- scanning speed: max. 10 000 nm/min
- digital integration time: 0.1 msec – 30 sec
- CPL felbontás 0,00001 mdeg
- full scale: ± 8000 mdeg
- scattered light: 0.001%
- shutter for both Ex and Em side monochromators
- built-in mercury lamp for checking the instrument
- sample compartment size: 150x310x165 mm
- control: Spectra Manager software
- computer communication: USB 2.0
- dimensions: 200x70x100 cm; 180 kg
