3 Facts About LED Optics and The Impact of Ultraviolet Light

  •  

Learn how to achieve a high intensity beam of light with UV LEDs for NDT inspection  

By David Geis, Accessory Product Manager

An LED by itself, without optics, emits light in all directions. That may sound like a favorable property because it means an LED will light up a wide beam. However, the problem for NDT inspection with this type of LED is that you don’t get much intensity at any one spot. That’s acceptable for background illumination, but for inspection you need to meet minimum intensity limits set by standards committees.  

LED Optics are the solution – the optics focus the LED light into a usable more concentrated beam. For a UV LED lamp to be useful for NDT for inspection, there needs be an optic over the LED source to provide a useful intensity. 

1. Optics must be selected to balance intensity against beam profile 

By reviewing the illustration, it is apparent that there is a design trade-off involved. Wide-angle beams provide smooth and even profiles, but narrow-beams provide the intensity needed for fluorescent inspection. A well-designed LED inspection lamp needs both for the best results. 

 

2. Common LED optics are made from PMMA 

UV-A LEDs present an extra challenge for optics. Common LED optics are made from PMMA (acrylic) – it’s cheap, easily molded into the required shape, and transparent for visible light. However, PMMA absorbs UV and will solarize (yellow and cloud over). The same phenomenon can be seen in older automotive headlights - with exposure to the UV from the sun the clear plastic becomes cloudy.  

 

3.Optics originally developed for UV LEDs are treated to transmit UV-A down to 320 nm 

With the special treatment optics will still solarize over time. Solarized lenses will severely decrease the output of an LED lamp, and that’s why low-cost UV LED lamps needed replacements on a regular basis 

Lamp manufacturers need to balance all these factors into the design of an inspection lamp that (A) has a useful intensity, (B) has a beam with a smooth and even profile without hot spots, and (C) is long-lasting and durable.  

With the EV6000, Magnaflux developed custom LED optics made from UV stable material. That means the lenses will not solarize and the UV-A intensity will not degrade over time. All LED UV-A Lamps from Magnaflux use these custom optics for dependable performance and a long life. 

 

 

Published March 5, 2019 

Please wait while we gather your results.

Related Blog Posts

Key Sustainability Issues for NDT

Key Sustainability Issues for NDT

As the NDT industry continues to modernize and evolve in the 21st century, sustainability has become a hot topic. For suppliers and consumers of NDT products, evaluating and adjusting processes and products, investing in innovative technologies, and putting sustainability at the forefront are critical.

Read More...

What You Need to Start-up In-house Testing [Checklist]

What You Need to Start-up In-house Testing [Checklist]

Step-by-step process listing everything from the equipment needed in magnetic particle testing and liquid penetrant testing to preparation for NDT audits

Read More...

Learn how to achieve a high intensity beam of light with UV LEDs for NDT inspection

NRTL: What Does It Mean and Why Does It Matter?

NRTL stands for Nationally Recognized Testing Laboratory, but what does that mean to you?

Read More...

Shedding Light on ASTM E2297 & E3022: A Guide to NDT UV Lamp Standards

An overview of two of the most common standards for NDT UV light sources, ASTM E2297 and ASTM E3022.

Read More...

How to Select the Right UV-A Lamp for Your NDT Needs [Checklist]

4 things to consider when looking for a new LED UV light for fluorescent penetrant inspection or magnetic particle testing.

Read More...

Understanding Safety Data Sheets

Understanding Safety Data Sheets: Do You Know What’s in the Chemicals You Handle?

We highlight the 5 major sections to understand on a Safety Data Sheets (SDS) in accordance with US OHSHA Hazcom 2012 GHS regulations

Read More...

Understanding the Magnaflux Shelf Life Statement for NDT Chemicals

Understanding the Magnaflux Shelf Life Statement for NDT Chemicals

Answering popular questions regarding shelf life for magnetic particle and liquid penetrant products used in nondestructive testing

Read More...

Why Does ASTM E3022 Require a Filter for LED UV Lamps?

Learn about the function and importance of UV-a pass filters, and why ASTM E3022 requires all LED UV-A lamps to have them.

Read More...

Handheld LED UV Lamps

About the EV6000 Handheld LED UV Lamp

Check out how Magnaflux’s EV6000 stacks against other leading UV-A portable handheld lamps in the market

Read More...

EV6000 Hand-held UV Lamp Demo and Q&A [Webinar]

Watch and listen to a 20-minute EV6000 demonstration by two outstanding NDT experts who afterwards host a 20-minute Q&A for participants to ask their own LED UV questions.

Read More...

ST700 Hood Mount is a freely-adjustable mounting frame

New Mounting System for Overhead UV-A Lamps

The ST700 Hood Mount is a freely-adjustable mounting frame to give operators the option to position their overhead UV-A Lamp to optimize inspection ease

Read More...

Magnaflux ST700 Overhead NDT Inspection Lamp

Stationary LED UV Lamp for NDT Inspections

See how the ST700 UV inspection lamp​ can eliminate the most common UV illumination challenges fluorescent NDT testing

Read More...

Learn how to achieve a high intensity beam of light with UV LEDs for NDT inspection

3 Facts About LED Optics and The Impact of Ultraviolet Light

Learn how to achieve a high intensity beam of light with UV LEDs for NDT inspection

Read More...

4 Monthly Checks Required for all LED Inspection-Grade Lamps

4 Monthly Checks Required for all LED Inspection-Grade Lamps

User-check requirements for LED UV-A lamps, and how to plot the beam of an LED UV-A lamp for Airbus AITM6-1001 Issue 11

Read More...

Complying with Airbus AITM requirements – How to check UV stability

Complying with Airbus AITM Requirements – How to Check UV Stability

Learn how to comply with the new requirements of the latest revision of Airbus AITM 6-1001

Read More...

Defining IP Ratings for Electronics Used in Mag Particle Testing & Liquid Penetrant Testing

Defining IP Ratings for Electronics Used in Mag Particle Testing & Liquid Penetrant Testing

In this article, we break down the ANSI/IEC 60529 Ingress Protection Code with a chart to show what's essential for NDT equipment

Read More...

NDT UV LED Lamps

Frequently Asked Questions About NDT UV LED Lamps

Frequently Asked Questions About NDT UV LED Lamps

Read More...

Nadcap AC7114 Rev J

How to Comply with NADCAP AC7114 Requirements for LED UV Lamps

An overview of Rev J changes to Nadcap AC7114 Non-Destructive Testing audit checklists for Penetrant and Magnetic Particle

Read More...

Airplane Engine NDT

How to Improve Fluorescent NDT Process Control with LED UV Lighting [Case Study]

See how an aerospace OEM manufacturer increased NDT inspection reliability & control with wide-beam, overhead LED UV-A lamps

Read More...

ST700 High Volume Inspections

How to Increase High-Volume NDT Inspection Speed and Reliability with LED UV Lighting [Case Study]

See how an automotive parts manufacturer decreased inspection time and improved reliability with wide-beam, overhead UV lamps

Read More...

Dye Penetrant Testing on Pipe

NDT UV Lamps “Stabilize” vs “Warm Up”, What’s the Difference?

Understanding the difference between NDT mercury-vapor lamp “warm-up” time and LED black light “stabilization” time

Read More...

New High-Intensity, Dual-Light LED UV Lamp for NDT Pros

Learn about how the EV6500 UV lamp for nondestructive testing improves visibility & versatility while minimizing time to inspect parts

Read More...

ST700 Overhead Inspection UV Lamp

New Stationary LED Inspection UV Lamp for NDT Pros

Learn how this new UV lamp for nondestructive testing solves the biggest challenges in fluorescent NDT UV illumination.

Read More...

UV-A Intensity: What’s Special About 5,000 µW?

UV-A Intensity: What’s Special About 5,000 µW?

Most UV-A lamps on the market are set to provide 5,000 µW/cm2 at a distance of 15 in / 38 cm. What’s so special about those numbers?

Read More...

Why Do I Get Over 2 Foot-Candle / 20 Lux Visible Light from My LED UV-A Lamp?

Why Do I Get Over 2 Foot-Candle / 20 Lux Visible Light from My LED UV-A Lamp?

A quick history of the visible light emissions requirement, where it is today, and an overview of UV meters

Read More...

JOIN OUR MAILING LIST TO RECEIVE THE LATEST NDT INSIGHTS AND ARTICLES FROM MAGNAFLUX

Magnaflux

155 Harlem Avenue
Glenview, IL 60025, USA
Telephone: +1 847-657-5300
Contact Magnaflux Customer Service

Select Your Country North America Mexico Brazil China Europe India New Zealand, Australia, Japan, Southeast Asia
© 2024 Magnaflux - All Rights Reserved.
top