Optical Convex Condenser Lens for Overhead Projector, Stage Lighting and Lighting Instruments

Optical Convex Condenser Lens for Overhead Projector, Stage Lighting and Lighting Instruments

1. Core Material & Design:

• Material: Made from clear, high-transmission optical glass (e.g., soda-lime crown) or high-temperature resistant glass (e.g., borosilicate for lighting).

• Design: A plano-convex or bi-convex lens, characterized by a curved surface that converges light rays.

2. Defining Physical & Optical Properties:

• Positive Focal Length & Convergence: As a converging lens, it bends incoming light rays inward to meet at a focal point.

• High Light Collection Efficiency: Its curved surface gathers light from a broad area, concentrating it into a more intense, directed beam.

• Heat Resistance (Lighting Applications): Variants for stage/studio use are tempered or made from materials like borosilicate glass to withstand intense heat from halogen or high-power LED sources.

• Optical Clarity: Features minimal bubbles or imperfections to reduce scatter and maximize light throughput for bright, clear projection.

3. Primary Function in a System:

• Condensation & Illumination: Acts as the core condenser lens in an optical train, collecting and focusing light from the source (lamp, LED) to uniformly illuminate a target plane (e.g., a slide, gobo, or LCD panel).

• Efficiency Enhancement: Maximizes system efficiency by directing as much of the source's light as possible through the projection gate or aperture, increasing overall brightness.

• Beam Control: In lighting instruments, it helps shape the raw light into a preliminary beam before further refinement by other lenses (e.g., a Fresnel lens).

4. Target Applications & Instruments:

• Presentation & Education: Overhead projectors (OHP) and modern digital overhead/opaque projectors.

• Stage & Studio Lighting: Fresnel spotlights, followspots, and ellipsoidal reflector spotlights (ERS/Lekos) as a key internal condenser element.

• Photographic Enlargers: Used in darkroom equipment to evenly illuminate a photographic negative.

• Specialized Scientific Instruments: In microscopes (as part of the condenser system) and other optical illuminators.