A double beam spectrophotometer is utilized by the scientific community to help simplify spectrophotometry. This is one of the key benefits of two beams of light versus a single beam spectrophotometer. Many applications that require characteristics such as high speed, stability, and flexibility are better suited for the dual beam configuration. The measurements taken with a double beam spectrophotometer tend to be more reproducible, making them a much appreciated boon to a number of industries. Benefits such as the above mentioned are especially useful in applications where strict guidelines must be followed and high standards must be met.
Spectrophotometers are utilized to measure light via wavelength distribution. Chemists, biologists, and physicists, among others, use these devices for visible light measurements as well as near-infrared and near-ultraviolet light. The double beam spectrophotometer was developed as scientists searched for techniques that would increase the resolution and speed of their measurements. Employing a dual beam setup means that both the sample beam and the reference beam can be measured at the same time.
Measuring the reference and the sample beam simultaneously or alternately, depending on the equipment configuration, increases the speed with which measurements can be taken. It also decreases the number of errors that can creep into measurements over time when using a single beam configuration. Single beam spectrophotometers must be zeroed out, or calibrated, regularly in between readings to help to avoid these types of errors. By using a double or dual beam setup, measurements and readings become more efficient and also decrease the chance for human error during setup and calibrations.
The design of the double beam spectrophotometer can employ one or two monochromators, through which the light is diffracted into wavelengths. This allows for better flexibility in the utilization of the equipment. Dual beam configurations also provide more stability than their single beam cousins. The beam division facilitates precise and reproducible results with its stability and consistency.
Fluctuations caused by light sources, electronic devices, or detectors that would otherwise appear between measurements are not issues with a double beam spectrophotometer. This type of configuration is also typically simpler to operate than the single beam configuration. Strictly speaking, double beam and dual beam spectrophotometers are different design configurations. The dual beam utilizes two parallel detectors and measures the sample and reference simultaneously, while the double beam utilizes a single detector and measures the sample and reference alternatively. The alternating method of measurement is the most accurate method.