A logo projector, also known as a gobo projector, operates by projecting a beam of light through a metal or glass stencil called a "gobo" (short for "goes before optics"). The gobo contains a design, such as a logo, pattern, or image, which is then projected onto a surface.

Here's how it typically works:

1. **Light Source:** The projector contains a powerful light source, often an LED or a halogen lamp, which produces a concentrated beam of light.

2. **Gobo:** The gobo is a thin, heat-resistant stencil with the desired design etched or printed on it. It's placed in the light path of the projector.

3. **Lens System:** The projector has a lens system that focuses and projects the light onto a surface. The lens can be adjusted to control the size and sharpness of the projected image.

4. **Projection:** When the light passes through the gobo, the areas of the stencil that are opaque block the light, while the transparent areas allow light to pass through, forming the desired image.

5. **Projection Surface:** The projected image appears on a surface such as a wall, floor, or ceiling, depending on the orientation of the projector.

Logo projectors are commonly used in various applications, including advertising, branding, events, and entertainment venues, to project logos, messages, or decorative patterns. They're versatile and can create striking visual effects with relatively simple mechanics.