HO-ED-S-0203 CCD Based Constant Deviation Spectrometer

CCD Based Constant Deviation Spectrometer (For Arc Emission & Absorption Measurements) The apparatus uses CCD imaging instead of photographic silver halide films. It has become difficult to carry out silver halide film based spectroscopic experiments in class rooms due to the unavailability of consumables and hurdles in its processing. CCD imaging of the spectrum is a timely solution. Data acquisition is easy and fast. As most of the commercial spectroscopes are based on digital imaging, students get an exposure to the latest trends in spectroscopy. Mercury is used as a standard element in most cases. Knowing the wavelength, corresponding to different spectral lines, elements can be judged. Hartmann's method is employed to determine the unknown wavelength. If a transparent substance is placed between a continuous source and a spectrometer, the substance absorbs a certain part of the spectrum. Hence in the continuous spectrum of the source, a few dark lines or bands appear. This spectrum is called absorption spectrum of the substance. This method is useful for manufacturing as well as for academic experiments. Constant Deviation Spectrometer (Model No: HO-ED-S-0203) can be used for the study of spectral series viz. emission spectra of elements, absorption spectra of compounds, quantitative spectrum analysis etc. When a substance is heated, electrons first absorb energy, go to a higher energy level and eventually fall to a lower level, by emitting photons. Every element emits a characteristic spectrum of its own. There are certain important and prominent spectral lines associated with each element. These lines are used to distinguish one element from another. In the experiment to determine an element, spectrum of standard known source is pictured first. Experiment:    To measure the wavelength of absorption bands of KMnO4 and calculate it’s Hartmann's constant. The positions of spectral lines are usually measured in the direction of increasing wavelength. The constant d depends on scale setting, C on the range of spectrum and is a constant for the instrument. To determine these constant, we take three prominent lines of standard spectrum and equations are, A    =    (λ2 – λ1) / (λ3 – λ1) B    =    (d2 – d1) / (d3 – d1) C    =    [ (λ2- λ1) (d0 – d1) (d0 – 2) ] / (d2 - d1) d0    =    (B d3 - A d2) / (B - A) λ0    =    (Aλ3 - B λ2) / (A- B) Where, A, B, C, λ0, d0 are called Hartmann’s constants. Using these Hartmann’s constants, we can calculate the absorption band wavelength as λ    =    λ0 + [C / (d0 - d)]    To find wavelength of prominent lines of the emission spectra of copper, iron and brass. The wave length of the corresponding lines of the arc spectrum can be calculated using the equation;   λ    =    λ0 + [C / (d0 - d)] Specifications:  Optical Platform     Constant Deviation Spectrometer     Prism     Pellin Broca     Prism Material     N-SF1     Effective Spectral Range     380 nm to 750 nm     Spectral Resolution     0.1 nm     Accuracy     0.5 nm     Slit Options     Micrometer Controlled, Variable Slit (0 - 3 mm)     Stray Light     < 0.06 % @ 532 nm (< 0.1% overall )     Detector     Toshiba Linear CCD Array     Total Pixel Number     3648     Pixel Size     8 µm x 200 µm     Pixel Well Depth     100,000 electrons     Signal-to-Noise Ratio     1,000 : 1 (at full scale)     A/D Resolution     16 bit     Exposure Time     1.0 to 6,500 ms     Frame Rate     Upto 138 fps     Trigger Input     Yes (Optional)     PC Interface     USB 2.0     Software     Spectra QSR V2.26     Compatibility     Windows 7 or higher Features:    Modern, user friendly and precision design     Emission and absorption spectra can be observed     CCD imaging system     High-quality optics produce sharp and clear spectra