Before the truck home was created, we combined the performance of multiple dimensions, and finally the led came out with the title "the king." subsequently, many katyus stated that halogen lights looked more comfortable and leds were suffering。
Why are the halogen lamps so comfortable, and the tallest leds nobody buys? We're here today to talk about the importance of color temperature in addition to light。
As can be seen from the comments from the previous issue, many of the cartoonists indicated that halogen lamps looked the most comfortable, that some considered halogen lamps to be high, and that halogen lamps were highly permeable。
Why are the brightest leds unpopular and old halogen lamps being admired? Let's talk about the secrets of the lights。
Why do halogen lamps look the most comfortable
Spectrum frequency led
Why do we all think halogen lamps look more comfortable than led lamps, where a concept is involved -- the spectrum。
Simply put, after the light passes through the colour-dispersion system (the diamond mirror), we can see that the light is divided into seven colours: purple, blue, blue, green, yellow, orange, red, seven colours, and the seven colours, organized by wavelength or frequency, are called optical spectrums。
Spectral power comparisons of various light bulbs
Let's start with a spectral comparison of the light bulb. While human-made lights cannot be compared to the sun, halogen lamps are a source of thermal radiation and their spectrum is very close to the sun. As can be seen, spectral continuity of halogen lamps is significantly better than that of led lamps。
The led, as a source of cold light, is not a continuous spectrum, the lighting cannot be compared to halogen lamps, and naturally the halogen lamps are considerably less comfortable in their eyes。
In addition, continuous spectrums make external objects more natural and real under exposure. The absence of certain spectral leds would make the irradiated object look like a “fake” and the colour would be distorted to varying degrees。
And that's why we can advertise the colour of the product in some lamp advertisements。
For visibleness, it means that different colour characteristics are presented when light sources from different spectral ranges are exposed to objects of the same colour. The colour index (ra) is usually used to indicate the colour of the light source. The higher the visible index of the light source, the more visible it is, the more true the color of the object. There will be no more discussion here, and kagi's little encyclopedia will continue to be widely available if he is interested。
♪ all evil ♪
Another reason why the led light doesn't look comfortable is because of the pwm. Now, most of the led lights on board are pwm。
The so-called pwm, known as the pulse width modification, translates it to be a pulse-wide modulation, a technique for modulating analogue signals into pulses, and the pwm luminous led in the form of scintillation。
The speed with which pwm flashes is extremely high and the eyes are almost invisible, combined with the low cost of this method, is widely used for car lighting。
Although the majority of the population is unable to detect more than 80 hz flashes, the flashes that are still felt in the eyes can also cause fatigue and headaches. So that's probably why they say halogen lamps are more comfortable than led lamps。
There was also a news report that the owner of a mercedes in shanghai was fined for having been filmed to the taillight by the traffic police. The brake taillight of this mercedes car used the pwm mode。
Likewise, this volvofm led light is also a pwm light, which is visible in our video equipment. By contrast, there's no flashing of the shin lamps in the lens。
The difference between the frequency of pwm luminaries and the frame rate of our video equipment has led to an unrecognizable frequency flash on the camera。
In fact, it's easy to solve the problem of pwm modulus, using dc. The rationale for dc lighting is simple: to change the brightness of led lamps by increasing or reducing circuit power. There is no discussion here, and if you want to know, please leave a message in the comment area below, and we will speak separately, as appropriate。
Color temperature is the key
Colour temperature is a physical amount used to define light-source colours in lighting optical. That is, when a type of bold text is heated to a temperature with the same colour of the light that is launched by a source of light, the temperature of this type of bold text is referred to as the colour temperature of the light source, known as the colour temperature. Its units are shown as "k" (kelvin temperature unit)。
Colour temperature indicates only the spectral composition of the light source and does not represent the light intensity. The temperature is high, indicating that the short wave composition is higher and blue and green, and low, indicating that the long wave composition is higher and red and yellow。
Here are some of the common light-source temperatures:
1800 k: candles
2800 k: incandescent lights
3000 k: halogen and yellow light sunlight
5500 k: daylight at noon
6500 k: daylight light
We said earlier that the spectrum is seven colours of purple, blue, blue, green, yellow, orange, red, etc., in light of the visible light that we can see in our eyes, after the light is divided by the colour system。
As can be seen from the figure above, red, yellow, orange wavelengths are relatively long, so red light is the most penetrating, so the brake lights and fog lights on the back are red。
However, as lighting, yellow light with a medium wavelength is the best light for the eyes and has considerable penetration, so the original plant's large vehicle lamps, both thallium and halogen lamps, are more yellow. The colour temperature of this light is roughly between 3,000 and 5,000 k, ensuring not only good lighting but also maximum light penetration in the rain and snow。
Well, that's all for today's introduction to spectroscopy and color temperature. While leds are not spectrally comparable to halogens and halogens, regular plant leds are not weaker than halogen lamps in either color temperature or colour, and the high brightness and low energy consumption advantages of leds are unparalleled。
When selecting a light bulb, you should consider the brightness of the light together with the penetration of the color temperature. And the high-colored and hot lights may not have any effect at night, except to shake the eyes of pedestrians and drivers. (man/chu peng fei)
