This article was first published on What Platform is Worth Buying? Please follow this account to get more good articles. Author: artpic
The picture in the title (from the Internet) shows Wenzhou traffic police explaining to a driver who abuses his car lights why he cannot turn on high beam. It is well-founded and convincing. Similar activities are being carried out in many places to promote the digestion and absorption of theoretical knowledge by allowing high-beam drivers to actively participate in practice.
There are more than 8,000 words in the following article. If you want to read it in one go, please prepare your children and arrange your work in advance. I hope that the following content will be useful to you.
Preface
The longer I have been a driver, the more afraid I am of driving.
When a car is speeding on the road at a speed of 36 kilometers per hour, drivers (whether the car owner or nearby car enthusiasts) will think that the car is very tame, but you must know that this speed has reached 10 meters per second. This The speed indicator clicks, and you have crossed from one end of the road to the other.
In other words, if there are five Yao Mings lying in a row on the ground (connected end to end, each 2.26 meters), then you can run over the four and a half in front with just one click.
What if it were replaced by Ke Wenzhe? There must be more than five!
At high speeds, drivers are willing to have better night vision, so they all think of upgrading light bulbs.
The first was to use high-power halogen bulbs, but the reflector bowl was scrapped.
Later, xenon lamps were installed, but the unsatisfactory result was that there was a delay in the work. A second-level response was already considered fast, and we have already calculated it, at least 5 Yao Mings per second.
When LED lights dominate the world, the Highlight Party has a new weapon: various LED car lights.
LED car lights have three treasures: super bright, start in seconds, and low power consumption. LED lights have three disadvantages: astigmatism, glare, and rain and fog.
In the spirit of studying things and seeking knowledge, the author specially researched today to find out how many treasures this LED lamp has among the three treasures, and whether the three wastes should be eliminated or not.
Reasons to buy
Although I said so much in a high-sounding way at the beginning, I bought this LED light for two reasons. One was that I was annoyed by high-beam drivers, so I equipped one myself, and the other was that this LED light was cheap enough, so it was not worth buying it back. It can also be used as an ordinary light bulb.
In the past two or three months, this product has been promoted repeatedly. Due to a strange combination of circumstances, I only had time to place an order for two pieces. It was a huge loss and I have embarrassed all of you. I’m sorry. I’m sorry. .
Full screen 19, earlier there was 14
I placed an order for the H1 model for the first time, because my 307 is a high-beam H1 low-beam H7. I had already replaced them with Osram's Nightcrawler series a long time ago, and it has not broken even today. It’s just one light bulb, and as a valuable friend, I also have a whole new set of two pairs!
I bought an H1 and installed it myself, but I couldn't install it no matter what.
What's the problem? Because in the hole opened on the back of the 307 car light, the hole for the light is not centered, but is offset to one side. How to explain it? Forget it, I can’t explain clearly. Let me draw a cross-section diagram for everyone to see.
Understand, it’s stuck and you can’t push it in!
I returned the product angrily. There was no shipping insurance, so I paid 8 yuan for the return shipping out of my own pocket. It was a loss.
Therefore, there is a lesson here. Please pay attention to it. Before you plan to replace the LED light bulb, go to your car to check and confirm whether the holes and space are sufficient. Otherwise, if you buy the light bulb and it cannot be inserted, you will have to count on it to last for 7 days. Reason for return, what a hassle.
Introduction to the structure of live wire plug-in LED lights
What stuck with me just now is the heat dissipation part of the LED car light. Nowadays, there are two main structures of the radiator part of LED bulbs: active cooling by fans and passive cooling by heat sinks.
This is passive heat dissipation with the heat sink.
Almost all early LED car lights were of this type, relying on a metal (usually copper or aluminum) braided tape installed at the tail of the bulb to contact the heat sink to conduct heat to the heat sink to achieve heat dissipation. Since the interior of the car light is almost sealed (there are ventilation holes), this heat dissipation performance is relatively average. Therefore, it is gradually becoming rare now. Of course, major manufacturers still have ways to solve it, such as improving the heat conduction efficiency between the light source and the heat sink. Its advantages are very obvious: it can make full use of the space around the car light installation position, and the heat sink It is soft and has good shape adaptability.
However, now more and more fans on the street actively dissipate heat. Like below.
Let's not discuss the front light-emitting part first, let's talk about the heat dissipation part. This type has smaller heat dissipation fins at the rear. The heat is guided to the heat dissipation fins, and then the built-in small cooling fan blows the heat away.
So why do we need to dissipate heat? Because LED light sources are particularly afraid of heat. Although LED devices are said to generate less heat and have higher luminous efficiency, their structure determines that they are more resistant to heat. Do you think that any of these devices, including phosphors, transparent plastic protective layers, and electronic diodes, sound like they can be roasted by high temperatures? Therefore, although LEDs generate less heat (they can still burn people), they are more afraid of their own heat and must take the heat away, otherwise they will be "burned", that is, the light will be attenuated.
This concept is very different from that of halogen lamps. The filament of halogen lamps can withstand temperatures of several thousand degrees, but LEDs cannot.
So since heat dissipation is so important, there are gradually fewer and fewer LED lights using woven heat dissipation strips. At present, the relatively common big-name products include Philips' Starlight series products, which is the first picture above, and The lamps produced by other brands are basically fan-cooled.
There is a problem with fan heat dissipation: one is the life of the fan, and the other is the size of the radiator.
It's hard to say about the lifespan. We can only hope that the products of major manufacturers will have a long lifespan. Otherwise, once the small fan hangs up, the LED light will soon die, and you can't check the fan every day.
Then there is the size of the radiator. If the brand is reliable (which means the heat dissipation capacity is up to standard), I hope that the heat dissipation volume is as small as possible. For example, of the two types below, I would choose the shorter and smaller one.
Why? Because of the protruding cooling fan as shown in Figure 2, it may be against the dust cover at the rear of the car light. Here I will borrow the content from the product promotion page of Philips Star Yaoguang to make an explanation.
As mentioned before, car lights with active fans for heat dissipation are completely blown by the fan at the back. However, if the fan is longer and more protruding, the air inlet of the fan will be too close to the dust cover, causing the air inlet channel to be blocked or even completely blocked. , thus unable to dissipate heat, and the final result is that the lamp is damaged. For example, you may have heard that LED lights have light failure. What is light failure? It is generally believed that the light-emitting unit gradually begins to be damaged (but it is not completely damaged, for example, part of the phosphor fails and falls off, but the PN junction does not fail and can still emit blue light, and the gold wire does not burn out, and the entire lamp is still working).
However, some car lights, like the bulb with a huge radiator that I just pictured (Foshan Lighting Products), will be equipped with a special dust cover, so that the radiator is in the engine compartment, and the lamp head goes through the dust cover and is installed into the car light. And keep it well sealed, which I don’t like too much: Do you know the status of the CPU fan? That one is still indoors, it should be outdoors, in the engine compartment. Such a small fan, oh, how pitiful!
Let me go back and say a few words, why are there still more fans and less heat sinks? Because it is true that the passive heat dissipation efficiency of the heat sink is poorer, it imposes higher requirements on the process of the light-emitting unit, but many manufacturers cannot be so particular, so using a fan is a better choice.
Continue to discuss LED lighting units
After talking about heat dissipation, we mentioned the light-emitting unit at the end, so we will briefly explain the light-emitting unit.
The structure of LED light sources is the same. The light-emitting diode emits excitation light, and the excitation light stimulates the phosphor to also emit light. Then the two lights are superimposed together and become light that everyone can see.
Normally, to excite phosphors, high-energy particles or other high-energy rays are required. For example, our energy-saving lamps (fluorescent lamps) are bombarded with ultraviolet (invisible to the naked eye) produced after thin mercury vapor is broken down. White light phosphor inside the glass enclosure. The current relatively high-energy light wave of LED lights is only blue, which is within the range of visible light waves. Therefore, it is generally combined with yellow light excited by yellow phosphors. After superposition, people feel that they are seeing white light.
Therefore, this brings a problem: the light of the LED light lacks red light. The detection method is very simple. Nowadays, pure white LED light sources are not uncommon. You can find a red object and look under the pure white LED light source (those cheap, pure white LEDs that are often pushed on the site, etc., formal Table lamps (home lamps will be much better), you will find that the red is very pale.
Here is an animation, which is a promotional animation for a water plant lamp. We can see the spectral characteristics of LED lamps under the combination of different lamp groups:
We can also look at a picture, which shows the spectral characteristics of several common light sources:
As can be seen from the picture above, the spectral characteristics of halogen lamps used in automobiles are still very obvious. Compared with sunlight, it has less short-wavelength end (blue), which makes it look very yellow, and long-wavelength end (red) The richness is close to that of sunlight, so the color rendering is better (but the recognition effect is more yellow). The spectrum of common white LEDs has a sharp tip in the blue band. This is also mentioned in many eye protection promotional materials. of Blu-ray.
However, there is a tricky thing about LED lights: its spectrum is the yellow-green and blue-green spectrum that human eyes are most sensitive to. Therefore, the LED light source will make people feel bright and dazzling. However, since the overall energy contained is not high, it will be difficult to see the lighting effect (because of the so-called poor color rendering).
Moreover, there is another problem with LED lights, which is the so-called high color temperature, that is, the high K number. Generally, halogen lamps are yellow, mostly around 3000K. Reasonable xenon lights look very white, and the reasonable color temperature is generally 4300K-5000K. LED lights generally reach a stable 6000K, and the color temperature is higher than common car lights in the world.
Therefore, there is a very annoying problem, that is, the all-white LED lights have almost no lighting effect on the asphalt road after rainy days. The light shines, but the ground does not "light up" at all. This experience was gained while riding at night. The solution at that time was to replace it with a warm white flashlight.
This is why I dare not really challenge LED car lights until today: I think these lights are useless at all, especially when I need them most.
buy another one
After talking so much, it seems that everyone has forgotten where we started.
Yes, I bought a 19 yuan LED light, but I couldn’t install it and returned it. But because I was still curious about LED lights, I bought an H4 when they had another sale.
After I bought it home, my initial impression was that the LED light was indeed very white and bright.
Look at this picture. The picture on the left is an incremental halogen lamp that I have replaced. In my previous article, look for the "Blinding Eyes" chapter in the table of contents to see my introduction to this pair of car lights, including purchase links and actual measurement results. GIF.
In the picture above, it can be clearly seen that the headlight bowl of the left front light (right side of the picture) is very overexposed, and it is not just as simple as yellow light and white light.
A few days after putting a single LED on the car, I found that the LED light was indeed very bright, but I also found that the tangent line of the LED light seemed not as clear as the original car. It's really bright, because during the day, when the car in front of me is stuck in traffic, I can flash it with my headlights, and I can see the light flashing out (it's not an exaggerated effect of being illuminated brighter during the day, I can see the flashing) Feeling), in the past, halogen lamps were useless for flashing people.
But how effective are LED car lights when lighting is really needed - at night? I waited for a long time, but that store never released another 20 yuan coupon. I couldn't stand it anymore, so I gritted my teeth and bought my second LED car light at a sky-high price of 29 yuan (including the return, it was my third). Only)
Appearance Gallery
The box I received was very simple, nothing to criticize.
Two boxes? Yes, the two boxes, the appearance of the first and second boxes are completely different. So, um, very suspicious.
Opening the box, the golden appearance is a bit eye-catching. Fortunately, I have already returned one, and now I can bear it better.
In the picture above, the left is the LED light body, and the right is the H4 card holder. There are two white circles on the lamp body, so that the lamp body is stuck in the card holder. Almost all LED car lights are designed in this way, because the angle needs to be adjusted to make the light pattern of the car lights more suitable for your light bowl.
We installed the card holder and carefully compared the two bulbs. At this time, I am still looking forward to and confident about the future performance of LED lights in focusing light. First of all, this LED light bead is indeed very small. It looks almost the same as the filament of an ordinary halogen bulb. Looking at the height, when the installation plane is almost the same (white line), the low beam filament (green frame) and the high beam filament (Red box) The height and length are very close. So close that I can hardly tell the difference. I think from this perspective, the light pattern should not be bad.
What’s worth complaining about is the low-beam tangent shield, it’s so sloppy. We can compare the small light bowls of original halogen bulbs, and they are not on the same level.
Let’s talk about this halogen bulb for a moment. This is an enhanced bulb from Hella. It cost 88 yuan to buy at that time. After nearly 3 years of use, the filament is still smooth and clean, without any roughness, and the loss is very small. Moreover, we can still see , in this bulb, the beautiful reflective bowl that comes with the low-beam filament is small, but the shape and structure is still relatively complex, completely different from the two sloppy little wings that come with the LED lamp. Of course, we can also see that the silver coating on the top to prevent direct light from shining out has peeled off, and two or three years have still left traces. Today, when LED lights dominate, I have to ask them to take a rest.
Looking at the LED car lights, the small fan is very thin overall. I like this very much because it can be covered with the original dust cover. I think this is very important.
I personally still believe in some of the original factory designs, especially the universal designs, which require oversized air filter boxes, dust covers behind light bulbs, etc. These things are included in every car, and they must be meaningful, because it is not enough to discard them after modification. reason.
Next, the two sides of the light-emitting panels of this lamp are riveted together with a rivet. There is a certain thickness in the middle. According to the manufacturer, there is a thermally conductive material in the middle, which can transfer the heat generated by the LED unit to the fan part at the back. Six light-emitting units use so-called flip-chips.
The concept of flip-chip is actually not uncommon now because it has become popular, but in the application of LED light source packaging, it also has advantages compared to the old version.
I really can't find a clear picture. The so-called flip-chip LED means that the PN level is placed at the bottom of the chip, so that the entire chip can emit light and achieve better light efficiency. In the past, there was a concept of COB, which just spread multiple LED units together for packaging to achieve a larger area of light-emitting unit. This, in our own blindly modified car lights, the effect is not good, because the light-emitting unit The size is quite different from the original halogen lamp filament, so the original car reflector bowl cannot be held at all.
Fortunately, there are relatively few car lights that do this now. But having said that, the development of LED car lighting technology is really fast. Some early products disappeared from the market within a few years, but they still remain among users.
Okay, that’s it for the appearance, let’s happily investigate things and gain knowledge.
initial feeling
Let’s briefly talk about the installation first. What you need to pay attention to is to adjust the angle. The installation angle of LED bulbs is always to be installed vertically in the lamp bowl. For this type of H4 dual-light lamp, the small light-shielding plate blocks the filament or LED. The lower half of the unit, so that the light reflected through the lamp bowl is blocked by the upper half, creating a tangent effect. I can’t help but post this picture again. You can see how complicated the reflective bowl originally designed for halogen lamps is. It’s just such a small piece of metal with so many curved surfaces and edges. Therefore, the low beam tangent line is very clear.
As for the LED car light I have, after installing it in the car, the most troublesome thing is that the tangent line does not come out properly.
Let's see what's going on.
Install
The science man will have no problem changing the light bulb. If it's a girl, just go next door and find one.
My only suggestion is that you take off the small round mirror of the rearview mirror so that you can watch the operation of the light bulb spring in the car. It is much more reliable than just touching it with your hands.
Look, the one with visual guidance is much more advanced, isn’t it?
To install the LED, the first step is to separate the base of the lamp from the lamp, as shown in the picture below.
Then, install the right base separately. After installation, it will look like the picture below.
Generally, the base has positioning gaps (the H4 has three, because it is the one that needs positioning the most), so it is very important to install it properly and securely. After checking through the small round mirror that the buckle is in place, the lamp body can be installed.
Installing the lamp body is easier. Squat down, look at the hole from the front of the lamp, and just poke it in. That's it.
Of course, you must make sure that you poke it in place, otherwise the position of the light-emitting unit will not match, which is very bad. But it won't light up when it's just inserted, because we haven't plugged it in yet. The H4 bulb has a three-pin plug, the H7 has two plugs, but the H1 is more troublesome because the original bulb has a single plug.
Why is H1 troublesome? Because the halogen bulb of H1 has this appearance.
Poke a plug with the positive pole, and as long as the negative pole is firmly installed, it will naturally come into contact with the car body, and then it will be connected. It is a very safe design. However, in LED light bulbs, in order to be universal, the lamp body is a common part, and then equipped with different card holders to achieve different specifications of appearance, which can save processing costs. Of course, there is another important factor, that is, LED bulbs generally emit light from both sides. To adjust the direction of the lamp bead, the two light-emitting surfaces need to face the left and right sides respectively. Therefore, they are connected through sealing rings and buckles. Adjustment. So, for the H1 light bulb, the negative electrode and the lamp are disconnected, with an insulating sealing ring in between. Therefore, the LED bulb plug of H1 is two independent plug wires with different shapes. You have to pull out the other negative plug from near the H1 lamp bowl. Well, I won’t go into details without pictures. All riders who really want to use it, please pay attention and don’t think that the seller shipped the wrong product.
After the plugs are connected, start the car (important), check whether the lights are on and whether the fan is working properly (listen to the sound). Then, carefully plug the plug and control box back in while the power is on, and cover with the dust cover. Why such a dangerous operation? In order to prevent foreign objects from hitting the fan blades when you retract the cord, affecting heat dissipation. When the power is turned on, you will know if the fan blades are scratched.
So why start the car? Because, alas, my car battery was too old. When I was taking pictures to write a report, I didn’t start the car. It took a long time to take pictures, which caused the battery to lose power. Then, I replaced it with a new battery. Therefore, if you are not confident enough about your battery, you can consider testing it with the car started.
One more point, the correct installation posture of LED bulbs is as follows:
The light-emitting surface faces the left and right sides respectively. If it is H4, the reflective bowl is at the bottom to hold the lamp beads.
That’s it for the installation, simple right?
test
Looking at the picture above, you must be thinking the same thing as me, it looks unreliable. I'm really worried about this issue.
As mentioned before, LED car lights have three treasures: super bright, start in seconds, and low power consumption. LED lights have three disadvantages: astigmatism, glare, and rain and fog.
It is super bright and starts in seconds. I have already experienced this during the installation and simple trial. Then, I am still worried about the next three problems. I don’t want to be taught a lesson by the traffic police uncles, how embarrassing it would be. (Well, don’t escalate it to the point of harming others or yourself, let’s keep it simple first)
So I decided to give it a try.
It was a dark and windy night, so I quietly sneaked into an empty space with no one around, ready to start my investigation of things.
This open space is right next to where I usually park, about 3-5 meters away. Opposite is the white door of the garage, so I conducted the test here. After the test was completed, I found that the place I chose was very good because I could still push the car back to the parking space because the car ran out of battery and couldn't start.
I brought a camera with manual mode and planned to study the specific performance of new and old car lights by manually setting the exposure mode. At the same time, for the sake of rigor, I set unified exposure parameters for the following pictures: Shutter 1 /50, aperture 4.5 ISO 3200 The white balance is fixed at a setting value so that the color of the halogen light in the photo (as seen through the camera screen) is as close as possible to the real situation, so the subsequent photos are done to a certain extent. What you see is what you get, for everyone to compare.
First, of course, my 100% brightened Hella headlights.
The test of this car light is explained in one of my previous reports and accompanied by animations. You can experience the effect of this brightened light. For details, please jump to the directory "Bright Eyes" (also mentioned in the previous article)
Is it effective? Well, let’s take a quick look. That’s it. Let’s start with the low beam.
There is a relatively obvious tangent line. There is no stray light at all on the upper left side. The right side is slightly raised so that you can see the electric vehicles driving in the opposite direction on the roadside. Well, no, the manual says that the right side is raised to let you see the road signs.
Since the look and feel of the picture with this exposure was consistent with my on-site look, I chose this exposure mode and continued to take subsequent photos. All the shooting positions of this wall were taken from the driver's seat through the front windshield (filmed).
Look, if you only turn on the low-beam headlights, and a standing pedestrian looks at the headlights, this is how it feels.
Under this kind of light, the small note posted on the door by the unscrupulous advertiser (white text on a black background, really unbelievable) has this effect. This small label blocked part of the light when I took the photo, so I changed my position later. The camera position was different from this one, but the camera position behind it remained the same.
Switch to high beam and this is the effect on the wall.
And under the high light of this halogen lamp, if I stand on the opposite side of the car, this is how I feel.
Dazzling and uncomfortable. Under high beam, looking at the writing on the wall, there is not much difference.
Okay, let's put on the LED lights in the dark and the car is still in place. Let's take a look at the effect of the LED lights.
First come the low beam lights.
First a tangent. Well, there are still tangent lines, not bad, but there is some stray light on it. Then there's the brightness, which doesn't seem to be much brighter. Let's get out of the car and take a look. Um, something's not quite right... the experience isn't very good.
Next, we look at the psoriasis on the wall. Psoriasis is nothing to look at alone, the words are still the same, but the texture of the back door has been exposed so much that it cannot be seen.
Then, simply try the high beam again.
Um, haha... Hiding in the car, I can already feel that the front wall is overexposed.
Then let's get out of the car and take a look.
Help...help...
Let's talk about what's on our mind
Since scattered pictures may be inconvenient, let’s try to look at the animated pictures and try to summarize the conclusions.
The first is low beam.
Aside from brightness, first of all, the biggest change is the glare in the upper tangent. Judging from the photos, this brightness should not be a big problem.
Let's take a closer look at the surface of the wall.
It looks exaggerated when you look at the picture, but I personally felt it was not so obvious at the scene: I can know the brightness and the color change, but it cannot be as bright as the animated picture, which makes people feel dazzling. Why pinch? Because the human eye is equipped with advanced dynamic aperture.
When the light changes, the eyes will actively and quickly adjust the pupil size to adapt. Therefore, after using the new car lights, I will not immediately feel that my world is bright, not because my eyes In the case of new and old car lights, the aperture is different.
This brings about a problem: no matter how the seller promotes it, the buyer’s actual benefit is almost the same when using it. No problem.
The lamp bowl remains unchanged and the filament is in its original position, so the changes in light pattern are very limited. Coupled with the dynamic aperture of the human eye, in addition to the most obvious color changes during travel, I do not feel that my light is very bright after long-term use.
Therefore, this explains a question: Do those high-beam party members really not know that they have turned on high-beam?
They really don't necessarily know.
I remember that I was walking to the office in the parking lot of my unit and heard two colleagues discussing cars. One of them said that he was often flashed by others. People said that he was using high beams, but he didn't know it at all. Another colleague said, aren’t there indicator lights inside the car? He replied that there were so many lights and he couldn’t figure them out. (ta refers to gender to avoid gender disputes, not to insult the other party)
Hey, don’t you read the manual for something that can kill people anytime and anywhere?
High beams are harmful to people, and those car lights with too much glare are harmful to people, mainly by affecting the safety of the target vehicle (see the picture below to feel it).
Because it affects the other party's field of vision, the other party cannot judge the surrounding things. Because when the other person's eyes are illuminated, the pupils will naturally shrink, so at this time, it is impossible to see things in the dark. Many nonsensical traffic accidents at intersections are entirely due to the high beams in the opposite lane making it difficult to see. Therefore, I would also like to remind you that you must pay attention when there is high beam on the opposite side. If you are passing an intersection, you must slow down and observe more carefully. Because if there is an accident, it is not easy to catch the high-beam vehicle on the opposite side, and the responsibility lies with you. At the same time, it is also recommended that riders who are illuminated by high beams also turn on their own high beams to try to get a better view. At least, it can remind pedestrians who may be directly in front of you to pay attention to avoid.
The Yuanguang Party not only harms others, but also harms itself.
Over-bright headlights allow the eyes to adapt to a bright environment. When turning and changing lanes, the eyes must explore the surrounding darker environment. After all, no matter how bright the headlights are, they will only illuminate the road ahead unless you keep driving in a straight line. If you cannot identify objects hidden in the surrounding dark environment in time, then an unexpected situation will happen sooner or later (see the picture below to feel it).
On the other hand, if the high beam is on, when you make a U-turn or turn, your indicator light will be obscured by the halo, and your indicator signal (turn signal) cannot be recognized in the target lane, and more importantly, your indicator light will not be able to recognize it when you turn around. Guang, the other person just wants to escape, so how can he think of being polite to you? The Yuangguang Party may not have this kind of empathy, so as long as they grab it a little, accidents will happen (please continue to look at the picture below to feel it).
Finally, there is the problem of rain and fog. Car lights that are too white and too bright will cause big problems in rain and fog: it is difficult to distinguish between puddles on the ground and wet asphalt. In this regard, halogen lights will be much better. It's a pity for the author. I really want to test this result, but I have been waiting for it to rain at night for more than half a month, and there is still no movement. I can only express it with a picture I found online.
According to the photographer of this picture, he replaced an LED light with a halogen one. On the foggy mountain road, he felt that the scenery on the halogen side was clearer. It's hard not to see this conclusion from the picture. I don't have a chance to test it myself. I will only find opportunities to supplement it in the future.
