What technical indicators should be paid attention to in classroom lighting transformation
According to statistics, a student spends 60% of his time in school. For students, the school is their second home. In schools, lighting is an inevitable factor. Good lighting can make students devote themselves to learning with full enthusiasm, while poor lighting will affect students' physical and mental health and teaching efficiency. Therefore, the classroom lighting environment of elementary and middle school students should be close to nature and try to absorb natural light. In the case that natural light cannot be realized, artificial light sources should also be consistent with natural light! What are the main technical indicators of eye protection lamps for classroom lighting?
One, pay attention to stroboscopic
Stroboscopic flash refers to the periodic change of light intensity and brightness over time. If the eye protection lamp has a stroboscopic flash, the pupils will sometimes expand and sometimes contract. If you use this lamp for a long time, it will cause eye swelling and fatigue, and affect your eyesight. Usually, most of the lights we use use 50 Hz AC power and have stroboscopic. The naked eye can only observe stroboscopic flashes below 30 Hz per second. Therefore, strictly speaking, the eye protection lamp is not "flicker-free" as some advertisements say, but the frequency of flickering is relatively high. Our naked eyes cannot distinguish them. They are invisible stroboscopic flashes, and it can be considered that there are no stroboscopic flashes, but this does not mean that the screen will not flicker. Classroom lighting should be stroboscopic, high-quality LED light source with stable lighting under the condition that the naked eye cannot detect it.
Two, look at the color rendering
Color rendering refers to the color display under the illumination of a light source. The closer the display color is to natural light or standard light, the better the color rendering effect, and vice versa. The color rendering index is an index used to express the color rendering effect. According to the current recommendations of the International Commission of Illumination (adopted by the Chinese national standard), the high color rendering index is 100, that is, the color displayed by the light source is exactly the same as under natural light or standard light. The larger the difference, the smaller the value.
Three, look at the illuminance
When studying, the gaze area is under or too strong, the light distribution is uneven or the light source flickers indefinitely, and there is glare or reflection in the eye gaze area; too small or unstable gaze on the target will overload the eyes and cause visual fatigue. Students studying under low illumination and uneven illumination for a long time can easily cause visual fatigue. Visual fatigue can lead to deepening of myopia, double vision, easy reading, inattention, etc., which affects learning efficiency.
Four, look at the glare
Since LED lights are solid-state light sources, human eyes will feel glare, which is actually a kind of glare effect. The so-called glare refers to that the strong light emitted by the light source enters our eyes in various ways, which makes our eyes feel dizzy, blurred and dazzling. The light emitted by the eye protection lamp should be uniform and soft, with appropriate brightness, moderate light area, and uniform illumination. According to relevant requirements, the eye protection lamp is placed at a height of 40cm from the center of the desktop, and the geometric center of the light source is downward. When the horizontal distance between the observer and the geometric center of the light source is 60cm, the eyes cannot directly see the luminous light source, nor can they see the light source reflected from the inner wall of the lampshade, so as to avoid glare.
