High Precision Quartz Glass Photolithography Reticle Concentric Circle Pattern Photolithography Calibration Plate

Concentric circle transmission reticles are a specialized type of transmission-type optical calibration element. They use a highly transparent substrate to support concentric ring patterns, allowing the calibration pattern to be superimposed onto the image. These reticles can also function as spatial filters to constrain light, making them commonly used position and measurement reference elements in optical systems.

Their core structure includes an ultraviolet fused silica substrate, a chrome-plated concentric circle pattern, and—on most models—a central crosshair. Some products feature additional millimeter graduations on the outer ring, and the fifth ring is often designed as a dashed line for quick and easy identification of specific diameter positions.

• High precision
• High stability
• High contrast
• Good durability
• 90% transmittance
• Customizable in various ways

• Pattern Fabrication: Concentric circle patterns (usually accompanied by crosshairs) are typically created on the surface of a transparent optical substrate (such as optical glass or quartz) using vacuum coating (e.g., a high-reflectivity chromium film) or photolithography.
• Transmissive Design: The reticle primarily operates in the transmission light path, allowing light to pass through the transparent area for imaging. Depending on the process, it can be divided into positive reticles (the pattern itself is an opaque chromium layer) and negative reticles (the pattern area is left open for light transmission, while the rest is coated).
• Size Specifications: The rings usually have fixed diameter spacing (e.g., 0.5 mm, 1 mm, etc. per level) and are numbered or have a central crosshair to aid alignment.

• Microscope System Calibration: Quickly calibrating the magnification correspondence after changing objectives and correcting measurement reading deviations—a commonly used calibration tool for routine laboratory tests.
• Optical System Alignment: Serves as a beam collimation target, assisting in laser optical path coaxiality adjustment and quickly determining whether the beam coincides with the system's optical axis center.
• Industrial Vision Calibration: Used for camera radial distortion correction, providing sub-pixel-level positioning references. Widely applied in semiconductor wafer defect detection, PCB board hole coordinate measurement, and other scenarios.
• Precision Optical Instrument Support: Installed on the image plane of sights and telescopes, assisting in target center alignment and angular deviation measurement.