Use of illuminance meter and measurement report of UV test
1. Purpose of the experiment:
1. Understand the concept of irradiance and learn to use an irradiance meter.
2. Understand the proportion of ultraviolet rays of different light sources.
3. Learn to measure ultraviolet irradiance.
2. Experimental principle:
Visible light contains a certain amount of ultraviolet rays. The amount and proportion of ultraviolet rays are very important for the preservation of cultural relics. The ultraviolet irradiance meter is used to measure the content of ultraviolet rays.
3. Experimental materials:
Irradiance meter, light source, meter stick, etc.
4. Experimental content:
1. Measure the intensity of ultraviolet rays in different places indoors and outdoors.
2. Measure the ultraviolet intensity of different light sources at a certain distance, and calculate its ratio.
5. Matters needing attention:
1. When using the irradiance meter, pay attention to the selection of probes and buttons, and the order of gears from large to small.
2. The probe of the irradiance meter should be perpendicular to the light.
3. When changing the light source, pay attention to the temperature of the light source to avoid burns.
6. Experimental steps:
1. Measure the ultraviolet intensity in different places indoors and outdoors, and measure the data without glass shading, one layer of glass shading and two layers of glass shading at the window. The measurement results are shown in Table 1.
2. Measure the ultraviolet intensity at 20cm of the 40W incandescent lamp, and calculate the proportion of ultraviolet rays.
3. Measure the ultraviolet intensity at 20cm of the 100W incandescent lamp, and calculate the proportion of ultraviolet rays.
4. Measure the ultraviolet intensity at 20cm of the 18W energy-saving lamp, and calculate the proportion of ultraviolet rays.
5. Compare the ultraviolet intensity at 20cm of several light sources, calculate the ratio and compare.
Note: The unit of UV ratio is microwatt per lumen
7. Experiment impressions
The working principles of incandescent lamps and energy-saving lamps are different. As incandescent lamps, they are basically the same except for quantitative differences. In comparison, energy-saving lamps are more suitable for lighting and UV protection.
