What is luminous efficiency?How to calculate the light efficiency?What is the practical significance of light effect?Following China floor lamp factory to understand:
What is luminous efficiency
Luminous efficiency refers to the luminous flux output by the light source per watt (W) of electricity consumed, expressed as the ratio of luminous flux to consumed power, and the unit is lm/W.
The power in luminous efficiency usually depends on the situation. In the calculation method of luminous efficiency, the power can refer to the radiant flux output by the light source, or the energy (electric energy, chemical energy, etc.) that provides the light source.Radiant luminous efficiency refers to the efficiency of light source to provide visible light, that is, the ratio of luminous flux to radiant flux;The luminous efficiency of a power source is a measure of the efficiency of the light source that provides the electrical energy to emit visible light, that is, the ratio of the radiant flux to the input power.
How to calculate the light efficiency
1, power efficiency (eta) P
Power efficiency refers to the launch of the light output power P0 and input excitation power Pi (optical power, beam power, the electric power injection, etc.) the ratio of eta P = P0 / Pi, is a dimensionless constant of less than 1.
Since most luminaries are used for display and lighting, their functions are measured by the human eye, but the human eye only senses visible light and has a very different sensitivity to different wavelengths. Therefore, luminaries with different emission spectra, even if they have the same power efficiency, see different brightness to the human eye.To reflect the differences in such photometric efficiency eta 1 are available, and it is the light of luminous flux Ф (lumens) and the ratio of the excitation power Pi, eta 1 = Ф/Pi, units for the lumens/watt.
Obviously, if the emission spectrum of the luminator is known, the power efficiency and the photometric efficiency can be converted into each other.
2, quantum efficiency (eta q)
In the research on the basis of the luminous body, especially for Yu Guangzhi glow and injection electric light, commonly used quantum efficiency eta q characterization of luminous efficiency.Quantum efficiency refers to the light emission photon number N0 and stimulate the absorption of the photon number or injection of electronic (hole) the ratio of the Ni: eta q = N0 / Ni, is a dimensionless number.
For photoluminescent materials, the quantum efficiency and power efficiency can be obtained by table formula when excitation and emission of homogeneous monochromatic light or near-monochromatic light.
Practical significance of light effect
1. Due to the structure of the human eye, the optical visibility of all wavelengths is not the same, and the spectra of infrared and ultraviolet light do not affect the luminous efficiency.
2. The luminous efficiency of the light source is related to the ability of the light source to convert energy into electromagnetic radiation and the ability of the human eye to perceive the radiation emitted.
3. The higher the luminous efficiency is, the higher the conversion efficiency of its electric energy into light is, that is, the less electric energy is consumed by emitting the same luminous flux. Therefore, when choosing an energy-saving bulb, the value of luminous efficiency should be used to make the final judgment standard.
4. According to Chinese standards, the rated luminous flux of 15W general lighting bulb is 110lm, and the rated consumption power is 15W. According to this calculation, the luminous efficiency is about equal to 7.3lm/W.
Above is the floor lamp lighting knowledge – luminous efficiency of the introduction, I hope you have some help;We are a Chinese floor lamp manufacturer, our products are:copper floor lamp,pharmacy floor lamp,globe floor lamp;Welcome to consult!
Post time: Jan-14-2020