General Requirements and Classification of Illumination Meters
How does a light meter work?
A germanium photocell is used as a probe. Due to the different intensity of light, the current generated by the photocell is different. This current is then DC amplified, and then the DC signal is converted into a digital signal that directly reflects the intensity of the light through a digital-to-analog conversion circuit and displayed.
General requirements for light meters
1. Small size and light weight (CompactSize, LightWeight)
The opportunities for use of illuminance meters are very wide, and the timing of use is often in different places. Therefore, the first prerequisite for a portable illuminance meter is its small size and light weight.
2. Accuracy
Whether a light meter is good or bad has an absolute relationship with its accuracy. Of course, it is also closely related to its price. Therefore, it is necessary to buy a high-accuracy illuminance meter at a reasonable price. Generally, it is appropriate to have an error of no more than ±15%.
3. Color Compensation﹝ColorCompensation﹞
The types of light sources are all-encompassing. Some focus on red high-pressure lamps with longer wavelengths, or blue-violet lamps with shorter wavelengths such as Daylight fluorescent lamps. There are also evenly distributed ones such as incandescent light bulbs. The same illuminance meter may have slightly different sensitivity to different wavelengths. are different, so appropriate compensation is necessary.
4. Cosine Compensation﹝CosineCompensation﹞
As we all know, the brightness of the illuminated surface is related to the incident angle of the light source. In the same way, when measuring with a light meter, the incident angle of the sensor (Sensor) and the light source will naturally affect the reading value of the light meter. Therefore, whether a good illuminance meter has the function of cosine compensation cannot be ignored.
Classification of illuminance meters
1. Visual illuminance meter: It is inconvenient to use, has low accuracy and is rarely used.
2. Photoelectric illuminance meter: Selenium photovoltaic illuminance meter and silicon photovoltaic illuminance meter are commonly used.
Application of light meter
1. Application in general public places
In order to ensure that people can live under suitable light, our country has formulated health standards for indoor (including public places) illumination, and uses illuminance meters to measure illumination in various places.
2. Lighting production industry, photography industry, stage lighting layout, etc.
Illuminance meters have been successfully used in many projects, such as lighting production industry, photography industry, stage lighting layout, etc. Different models of illuminance meters can meet different measurement requirements.
3. Factory production line application
In factories, the illumination requirements on the production line are relatively strict. Continuous work will cause visual fatigue and greatly reduce work efficiency. Usually the illumination requirement is ≥1000Lx. For places with relatively high illumination requirements, you can choose a large-range illuminance meter with an ultra-large range. Can handle strong light illumination measurement.
4. Illuminance meters are widely used, including applications in our daily lives, such as factories, warehouses, schools, offices, homes, street lighting construction, laboratories, etc.
