What is the measurement principle of a lux meter?
Also known as a lux meter, it is a specialized instrument for measuring illuminance. It is to measure the degree to which an object is illuminated, that is, the ratio of the luminous flux obtained on the surface of the object to the illuminated area. An illuminance meter is usually composed of a selenium or silicon photovoltaic cell, a filter, and a microampere meter.
measuring principle
A photovoltaic cell is a photoelectric component that directly converts light energy into electrical energy.
When light is incident on the surface of the selenium solar cell, the incident light passes through the metal thin film 4 and reaches the interface between the semiconductor selenium layer 2 and the metal thin film 4, generating a photoelectric effect at the interface. The magnitude of the generated photocurrent is proportional to the illuminance on the surface of the photovoltaic cell receiving light.
At this point, if an external circuit is connected, a current will flow through, and the current value will be indicated on a microampere meter with lux (Lx) as the scale. The magnitude of photocurrent depends on the strength of the incident light. The illuminance meter has a gear shift device, so it can measure both high and low illuminance.
Types of illuminance meters:
1. Visual lux meter: inconvenient to use, low accuracy, rarely used
2. Optoelectronic lux meter: commonly used selenium photovoltaic cell lux meter and silicon photovoltaic cell lux meter
Application scope
In order to ensure that people can live in suitable lighting conditions, general public places should be used,
China has established hygiene standards for indoor (including public places) illumination, and uses illuminance meters to measure illumination in various places.
Lighting production industry, photography industry, stage lighting arrangement, etc
Illuminance meters have been successfully applied to multiple solutions, such as the lighting industry, photography industry, stage lighting layout, etc. Different models of illuminance meters can meet different measurement requirements.
Application of Factory Production Line
In factories, the lighting requirements on production lines are relatively strict. Continuous work can cause visual fatigue and greatly reduce work efficiency. Usually, the illuminance requirement is ≥ 1000Lx. For places with high lighting requirements, a large range illuminance meter can be selected, with a super large range that can cope with strong light illuminance measurement.
The application of illuminance meters is very extensive, including our daily life applications such as factories, warehouses, schools, offices, homes, streetlight construction, laboratories, and so on.
Illumination standards for offices, roads, and specific environments
The JIS standard provides recommended illuminance values that can adapt to various environments. The following are the standard values set for it
