The reticle is generally mounted on the sighting device. It is a thin glass with a line of densely-divided lines engraved on the surface of a polar book.  Often used in sights, telescopes, microscopes or measuring equipment. Features such as participation in imaging, inspection, measurement, positioning and calculation of target distance. In modern use, the reticle is almost custom made. Because the pattern on the reticle is important, it determines the sight and accuracy .

　　There are many kinds of patterns on the reticle, including wire crosshairs, etched crosshairs, illuminated crosshairs, etc. Traditional thin cross lines are original, but they are best suited for precise aiming and achieving high contrast targets. But thicker stripes make it easier to distinguish complex backgrounds, each with its own advantages. However, the most popular crosshair type in the modern range is a variant of the double-sided crosshair, which has a thicker peripheral stripe and a thinner middle. The thick strip allows the eye to quickly position the center of the reticle, and the thin lines at the center allow for precise aiming. Movies and media often use reticle as a view of dramatic equipment, which gives the reticle a broad cultural background.