Helpful Tech Tips and Tricks
It is important to figure out which type of the headlight housing is installed to your vehicle, before upgrading the headlights. We’ve been talking about the sealed beam type of the headlight housing in one of our articles. Today we would like to tell you about reflector and projector headlights.
We will start with the reflector type of the headlights. They come with bulbs that are filled with mixture of the inert gas or Xenon gas. Most of them come with plastic lenses, but there may be exceptions. They are used to prevent the moisture from entering the headlight assembly and increase the intensity of the headlight beam. The only removable parts are bulbs. The rest of the housing is sealed unit. Inside the housing there are openings where the bulbs are inserted and locked into place.
The design of the reflector is pretty simple: it consists of a light source (headlight bulb) that is situated in the middle of the reflector cup. The light reflects from the surface directly outwards in one direction. It is distributed in many different angles. This allows the light being emitted from the small bulb to be spread out in front of the vehicle. The reflectors allow the driver to see clearly when it is dark, but on the other hand, they present a hazard for oncoming traffic. This type of the headlight housing involves a lot of wasted light. The reflector dissipates the light that is available evenly, but not all beams are directed properly and can be reflected too far up or down and be not visible to the driver.
Now let’s move on to the projector headlights. They have elliptical reflector, lens, light source and cutoff shield (low beam projectors).
The projector headlight refocuses the reflected light and directs it through a concave lens. Drivers get better light output with this type of the housing because the light is more controlled. The lens straightens out the path of the light, as it directs every beam in the same direction. The noticeable thing about the projector is the low beam cutoff line that is projected when the lights are switched on. There is a shield inside the projector. It serves as a light barrier so that the light is concentrated out and down. The cutoff shield keeps the light from being projected out and up. The high beam projectors come without the light barrier, so that the light is concentrated when it goes through the lens.
Nowadays many automotive sellers offer so called dual beam projectors.
They perform for the high and low beam taking single beam bulb. You are able to switch from the low to high beams due to the movable metal shield which is controlled with solenoid. It is a sort of motor within the headlight assembly that raises and lowers the shield.
The other possible way for the projector to perform for high and low beams is change of the bulb position. The bulb can be physically raised in the reflector housing to produce the high-beam output. In the low-beam mode the bulb is lowered in the reflector housing. In this case the amount of reflection dictates the light intensity and pattern.
Using the same bulb for both beams (high and low) permits both modes to have the same light color. This produces less visual contrast when switching between modes and is less stressful to the driver’s eyes.
At the end we would like to sum up the info about these types of headlight housings. The reflectors have pretty simple design, which allows the light to be scattered evenly. The field of vision is wide enough, but at the same time, the light pattern has intense and weak spots and the low beam cut off is blurred which may cause the blinding of oncoming traffic.
As for the projectors, this type of the headlight housing has complicated constructions, comparatively to reflectors. The light output does not have intense or weak spots. Its pattern is more concentrated and is more pencil beam like which prevents blinding of other drivers.