Longpass Filters for Vision inspection Apllication

A band pass filter is a device that passes frequencies within a certain range and rejects (attenuates) frequencies outside that range, and it’s used to selectively transmit a portion of the spectrum while rejecting all other wavelengths.

A Neutral Density filter allows a photographer to control the exposure in an image very easily. The filter stops light reaching the camera sensor, therefore allowing us to leave the camera with a higher aperture for a longer amount of time.

1、What Metallic Coated types can Uni-Optics supply?

Uni-Optics mainly offers four coating types, including:

1) UV Enhanced Aluminum : Ravg > 85% from 250nm to 400nm

2) Protected Aluminum: Ravg > 87% from 400nm to 800nm

3) Protected Silver: Ravg > 95% from 400nm to 20um

4) Protected Gold: Ravg > 98% from 650nm to 16um

2、What are the features of Metallic coated mirror?

Metallic coated mirror have many key features below:

Wide spectral range

Not sensitive to the incidence angle and polarization state

Low cost

Non-durable

Relatively low reflectance

Low laser damage threshold

3、What UNI Optics can do for you?

Common Specifications:

Substrate Materials: N-BK7, Fused silica, Pyrex；Float glass

Dimensional tolerance: +/-0.1mm

Surface quality:  60-40

Parallelism:  3’

Flatness: λ/4 per 25mm@633nm

Bevel: Protective

One surface: Polished and Metallic coating

The other surface: Fine ground

Note: Aluminum is the most widely used metal reflection film, from near UV to near IR, have high reflectivity, and with low cost. Silver has higher reflectivity in the visible and near infrared wavelength than the aluminum film, but the silver in the air will be rapid oxidation, color darkening, makes the film performance and firmness declined rapidly. Gold film has a good consistency with high reflectivity in the near, middle and far infrared range, can control the thermal radiation effectively, but it is relatively soft, easy bruising, and should be paid very close attention to clean, and the cost is very high.

For Intelligent Transportation Systems (ITS) Applications: Road Surveillance, ANPR/ALPR, Automatic Incident Detection, Traffic Enforcement Systems, Railway/Tunnel Safety Monitoring, etc.

· Excellent edge sharpness and uniform illumination
· Designed to resist strong light interference, adaptable to complex lighting conditions
· Ultra-high resolution,accurately capture license plates and facial details

Product information: Custom designs are available upon request.

For Automated Optical Inspection (AOI), Food Sorting, Recycling Sorting, etc.

· Developed for 1" image format
· Wavelength: 900-1700nm
· Large Aperture, upto F1.4
· Compact and lightweight design