There are many spectrophotometer products on the market today. Some are employed together with various analytical instruments. Some fit on the bench while others are used in many different industrial environments. Here we’ll check out two types of UV based products used in the lab setting.
PDA, or Photodiode Array spectrophotometers, processes a range of photodiodes to research the light emitted from transmission of light via a liquid sample inside the spectrophotometer. This leads to much smaller devices, right down to even handheld analyzers. This process is used in lots of UV spectrophotometer products today, and is a very precise instrument.
The application process could be explained as being a simple light detecting device which has a many detectors, each calibrated for a specific wavelength of visible or ultraviolet light. It can be consists of about six parts: The light source, often a tungsten lamp coinciding with a deuterium diode for UV detecting, a collimator to direct the light beam which then moves via a slit calibrated towards the instruments qualifications, the beam is reflected via a mirror to a grating consisting of calibrated prisms, which split the light into individual wavelengths. Then a light is transmitted to numerous specific photodiodes.
The source of light is placed in front of the sample, which is really a diluent or reagent combined with the material to be analyzed. This sample must be clear of debris and turbidity since this could hinder the analytical process. The light moves through the sample, causing absorption of the light through the sample, and then the beam is delivered to the grating, separating the light into its specific wavelengths. This in turn is reflected in the grating to a multi-channel detector consisting of the photodiodes hard wired to detect specific wavelengths of light.
The Scanning UV visible spectrophotometer has a different configuration. The light source is first reflected off a concentration mirror, then is split into the wavelengths of light driven by the prismatic grating. This divided light is sent to another focusing and concentration mirror. This light is then focused over the sample with a scanning mirror, and also the resulting absorption with the sample measured by way of a photoelectric detector.
Both of these instruments are capable of analyzing just about anything which can be dissolved into a diluent or solvent. Calibration is performed with a blank diluent placed in the instrument before analysis, thus giving the machine a reference point for analyzing the samples. These kinds of spectrophotometers products are used worldwide for various applications and disciplines.