Lens

Sourcing optical lenses for analog surveillance systems requires strict attention to optical precision, thermal stability, and sensor compatibility. Whether you are integrating fixed board lenses into standard dome cameras or sourcing varifocal CS-mounts for professional box cameras, selecting the right manufacturing partner dictates the final image clarity and low-light performance of your security hardware.

Key Specifications for Analog Security Lenses

Procuring lenses in bulk means aligning exact optical specifications with your target camera sensors. Even in analog systems (including high-definition analog formats like AHD, TVI, and CVI), optical resolving power is critical.

When specifying your order with a manufacturer, you must define:

• Mount Type: M12 (S-mount / board lenses) for compact and dome cameras, CS-mount for standard box cameras, and C-mount for specialized long-range applications.
• Format Size: The image circle of the lens must cover the camera's sensor. Common formats include 1/3-inch, 1/4-inch, and 1/2.7-inch. Using a lens with a smaller format than the sensor results in heavy vignetting.
• Focal Length & FOV: Fixed focal lengths (typically 2.8mm, 3.6mm, or 6mm) offer lower costs and wider apertures. Varifocal lenses (such as 2.8–12mm) provide installation flexibility but require complex mechanical assemblies.
• Aperture (F-Stop): Lower F-numbers (F1.2, F1.4) allow more light, essential for low-light analog surveillance.

Manufacturing Quality and Optical Precision

The difference between a premium surveillance lens and a lower-tier alternative lies in the manufacturing environment and element composition.

Element Composition: Glass vs. Plastic (G/P)

Lenses are constructed using a combination of glass (G) and plastic (P) elements. An all-glass (e.g., 4G or 6G) lens offers superior thermal stability. Security cameras operate in extreme environments; plastic elements can expand or contract with temperature changes, causing "focus shift" where the camera loses focus during hot days or cold nights.

IR Correction for True Day/Night

Analog cameras relying on infrared illumination for night vision require IR-corrected lenses. Because visible light and infrared light have different wavelengths, they focus at different points. An uncorrected lens will produce a sharp image during the day but a blurry image at night when the IR LEDs activate. Manufacturers achieve IR correction through specialized broadband anti-reflective coatings and specific glass dispersion properties.

To mitigate defect risks, rigorous quality control & inspection protocols should be implemented at the factory, focusing on optical testing before the lenses are sealed.

Customization and Supplier Vetting

If you are developing a proprietary camera housing or need a specific field of view, you may require OEM/ODM services to design a custom optical block. Custom lenses require new tooling for the lens barrel and potentially custom-ground glass elements, which increases upfront costs but secures a unique market advantage.

Before committing to a custom tooling fee or a large volume order, verifying the manufacturer's optical testing equipment and production capacity is non-negotiable.

Pricing, MOQs, and Lead Times

Lens pricing is highly dependent on the number of glass elements, the complexity of the mechanics (fixed vs. varifocal), and the aperture size.

• Fixed Board Lenses (M12): Highly commoditized. MOQs typically range from 1,000 to 5,000 units. Lead times are generally 2 to 4 weeks for standard specifications.
• Manual Varifocal Lenses (CS-Mount): Higher complexity. MOQs often start around 500 units. Lead times typically range from 4 to 6 weeks.
• Motorized Zoom Lenses: Used in PTZ analog cameras. These command the highest prices due to integrated stepping motors. MOQs can be lower (100 to 500 units).

Frequently Asked Questions

Procuring analog surveillance lenses in volume requires balancing optical performance with unit economics. By strictly defining your G/P ratios, insisting on IR correction for day/night applications, and verifying supplier cleanroom standards, you can secure reliable components that elevate your entire security product line.