for architectural lighting, as well as in interior design, as in projecting a company logo on a wall. Placement in "the gate" or at the "point of focus" is important because it produces a crisp, sharp-edged pattern or design (of logos, fine detail, architecture, etc.). Lighting designers typically use them with stage lighting instruments to manipulate the shape of the light cast over a space or object—for example, to produce a pattern of leaves on a stage floor. Gobos placed after the optics do not produce a finely focused image, and are more precisely called "flags" or "cucoloris" ("cookies"). Materials Gobos are made of various materials. Common types include steel, glass, and plastic. Steel gobos or metal gobos use a metal template from which the image is cut out. These are the most sturdy, but often require modifications to the original design—called bridging—to display correctly. To correctly represent the letter "O", for example, requires small tabs or bridges to support the opaque center of the letter. These can be visible in the projected image, which might be undesirable in some applications. Glass gobos are made from clear glass with a partial mirror coating to block the light and produce "black" areas in the projected image. This eliminates any need for bridging and accommodates more intricate images. Glass gobos can also include colored areas (much like stained glass windows), whether by multiple layers of dichroic glass (one for each color) glued on an aluminium or chrome-coated monochrome gobo, or by newer technologies that vary the thickness of the dichroic coating (and therefore the color) in a controlled way on a single piece of glass—which makes it possible to turn a color photo into a glass gobo. Glass gobos generally offer the highest image fidelity, but are the most fragile. Glass gobos are typically created with laser ablation or photo etching. Plastic gobos or transparency gobos can be used in LED ellipsoidal spotlights. These "LED-only" plastic gobos can be full-color (like a glass gobo), but are far less delicate. They are new to the market, as are LED lights, and their durability and effectiveness vary between brands. In the past, plastic gobos were generally custom-made for when a pattern requires color and glass does not suffice. However, in a "traditional" (tungsten-halogen) light fixture, the focus point position of a gobo is extremely hot, so these thin plastic films require special cooling elements