F-theta lens 4mm C-Mount lens for 2/3" sensors.

4mm C-Mount F-Theta Lens 2/3" 5MP

The CIL520 is a 4mm C-Mount lens for 2/3" 5MP sensors. The F/1.5 aperture makes this great for wide angle lens applications. Note: this lens does have distortion

$249.00

10pcs CIL520-F1.5-CMANIR (F/1.5 / Without Filter / C-Mount A) in stock in the US

In stock — orders before 12 PM PST ship same day

Optical and Mechanical Specification Table

Lens Parameter Performance Detail
Part NumberCIL520
EFL4.2
F# 2.0
Resolution8MP (2.3um)
Field of View153° @ 11.0mm Image Circle — Calculate FoV for your sensor
Image Circle11.0mm
Distortion0% F-Θ
Weight207g
IR Cut-Off FilterRemovable
ConstructionGlass+Plastic
Same Day Ship by 12 PM PST
US-Based Optical Engineering Support
25,000+ Stock in California
100% MTF Tested

Frequently asked questions

What sensors does the CIL520 4mm C-mount lens support?

The CIL520 is listed for 2/3 inch sensors up to 5MP. The focal length is 4mm and the aperture is F/1.5.

What part number is listed for the CIL520?

The page lists CIL520-F1.5-CMANIR, described as F/1.5, without filter, C-Mount A.

Is the CIL520 an M12 lens?

No. The CIL520 is a C-mount lens. Use it with cameras that support a 1 inch-32 C-mount thread and the normal 17.526mm C-mount flange distance.

Does the CIL520 have distortion?

Yes. The product note says the lens does have distortion. Measurement systems should calibrate the image instead of assuming rectilinear geometry.

Does the CIL520 include an IR cut filter?

No. The listed part number is the ANIR version, which means without filter.

Does the CIL520 ship same day from the US?

Yes. In-stock orders placed before 12 PM PST ship same day from the Commonlands San Diego warehouse.

The CIL520 is a 4mm C-mount lens for 2/3" sensors up to 5MP. The F/1.5 aperture gives useful light throughput for wide-angle machine vision when the camera cannot afford long exposure times.

This is a C-mount lens, not an M12/S-mount lens. Use it with cameras that support the 1"-32 C-mount thread and normal 17.526mm flange distance. If you adapt it to another mount, adapter thickness and sensor position become part of the optical setup.

The listed part number is CIL520-F1.5-CMANIR, described as F/1.5, without filter, C-Mount A. The product note says the lens does have distortion, so inspection or measurement systems should plan to calibrate the image instead of treating the lens as rectilinear.

Choose this lens when you need a short focal length C-mount option for a 2/3" 5MP sensor and can tolerate or correct wide-angle distortion. In-stock orders placed before 12 PM PST ship same day from San Diego.

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About Commonlands

Commonlands LLC designs and manufactures precision M12, C-mount, and M8 lenses for machine vision, robotics, and embedded camera systems. Based in San Diego, California, we stock inventory for same-day shipping and provide direct access to US-based optical engineers. Whether you need a single prototype lens or production volumes of 25,000+, our team supports the full lifecycle from optical design consultation through volume fulfillment.

Need help selecting the right lens for your camera module?

Contact our US-based Optical Engineers.