Transmission spectrophotometer

Transmission spectrophotometer decomposes white light into light of different wavelengths and measures the absorption of substances to obtain their absorption spectra and color information. It is widely used in fields such as chemistry, biology, and materials science to study the structure, properties, and reaction processes of substances

The transmission spectrophotometer decomposes white light into light of different wavelengths and measures the absorption of these lights by a substance to obtain its absorption spectrum and color information. Determine the color of a sample by measuring its absorption and transmission of light of different wavelengths (within the visible light range). When the sample is placed in the instrument, it will be illuminated by white light and absorb or scatter light of different wavelengths according to its composition. Then, by using detection equipment to record and interpret this information, provide data on sample color and other related parameters. Widely used in fields such as chemistry, biology, and materials science to study the structure, properties, and reaction processes of substances.

Correct usage method:

1. Before use, it is necessary to preheat and calibrate the transmission spectrophotometer. Normally, instruments need to be preheated for a period of time to ensure their stability and accuracy. At the same time, it is necessary to calibrate the instrument to eliminate errors in the instrument itself. Calibration usually includes adjusting parameters such as zero point and sensitivity, and specific operations can refer to the instrument's user manual.

2. Prepare the sample for testing. The sample should be pure and should be protected from external factors such as light, heat, and moisture. If liquid samples need to be measured, transparent glass or quartz colorimetric dishes can be used, and the sample should be filled in the colorimetric dish to avoid the influence of air layer on the measurement results.

3. Place the sample in the sample chamber. A sample room is usually a small indoor space with optical windows used to place samples and light sources. Before placing the sample, ensure that the sample chamber is clean and check if the optical window is clean to avoid impurities affecting the measurement results.

4. Choose the appropriate wavelength range and light intensity. The transmission spectrophotometer has adjustable wavelength range and light intensity options. Select the appropriate wavelength range and light intensity based on the characteristics and measurement requirements of the sample to be tested. In general, measurements can be taken starting from longer wavelengths and gradually moving towards shorter wavelengths to obtain complete absorption spectrum information.

5. Measure and record the results. Before conducting measurements, ensure that the instrument is in a stable state and perform background correction to eliminate the background signal of the instrument itself. Then, select the measurement mode (such as transmission mode or absorption mode) and start the measurement. During the measurement process, pay attention to the values displayed by the instrument and record the absorbance or transmittance values at each wavelength point.

6. After completing the measurement, promptly save and analyze the measurement results. Appropriate software can be used to process and analyze measurement data, such as drawing absorption spectrum curves, calculating absorbance peaks, etc. Meanwhile, pay attention to preserving the relevant information of samples and instruments for future reference and verification.

Regular maintenance methods:

1. Regular cleaning. Gently wipe the outer surface of the instrument with a clean, soft cloth or tissue to ensure that there is no dust or stains. Meanwhile, be careful not to use cleaning agents containing acidic or alkaline components to avoid damaging the surface of the instrument.

2. Regular calibration. Calibration can ensure the accuracy and reliability of the instrument's measurement results. During the calibration process, it is necessary to use standard samples for comparison and adjustment. The calibration frequency can be determined based on the frequency of use and the requirements of the instrument, and it is generally recommended to perform calibration once a month or quarter.

3. Regularly check the light source and light path system. The light source is a crucial component for the normal operation of a transmission spectrophotometer, and its brightness and stability need to be ensured. If the brightness of the light source decreases or becomes unstable, it should be replaced or repaired in a timely manner. The optical system includes the transmission optical path and detector, etc. It is necessary to check for impurities or damage, and clean or replace them if necessary.

4. It is also important to regularly inspect and replace the filter of the instrument. Filter is a key component used to select the wavelength of light that passes through, and may age or be damaged after prolonged use. Regularly check the condition of the filter and replace it as needed to ensure the accuracy of the measurement results.