A red dot sight is an effective classification for any kind of non-magnetic reflector sight for guns, which provides the shooter with a definite point of aim via an illuminated red dot, usually of the shape of a cross. These sights are ideal for target practice or hunting since they allow the user to see what he is shooting at, in good light, with minimum strain on the eye. The term "red dot" comes from the red dot found on military weapons.
There are several types of red dot sights. The first is a reticle sight, like that of a compound bow sight. The reticle of this kind of sight shows an outline of the target, usually with some kind of grid. The objective is at the center of the outline. It can be tilted for greater range accuracy or removed for increased brightness. This type of sight offers a very simple, compact design, ideal for portable usage.
Another type of red dot sight is called a laser sight. It uses a magnifying lens that projects a red dot on the target. In many cases, this kind of sight has a small illuminated target on the opposite end of the projected lens. This type of sight can provide much greater distance accuracy than a reticle sight.
A monocular sight uses a combination of cross and lamp technology to provide a crosshairs image of a target. When the crosshairs are touched by a finger, a dot appears on the corresponding eye piece. This sight offers less precise targeting than a dot reticle, but it has the advantage of being very reliable when the surrounding environment is dim or dark.
A monocular sight can also be used as a laser sight, although a laser crossbow is not often used with this type of sight. Red Dot sights use an electrical charge to produce a red dot at the focus of the lens. The electrical charge is generated by a diode, resulting in a phosphor that glows red. Once lit, the phosphors sublimate the light reaching the target, producing a faint red dot in the center of the crosshairs.
A monocular red dot is typically more expensive than a laser crossbow. Some models have a built-in laser option, which provides even better results at a lower cost. However, this is not always available. Many of these types of sights require a battery and a charger, as the electrical charge produced by the diode cannot be stored indefinitely. Monocular sights are more popular among hunters, because they offer more refined visual accuracy for the avid hunter.