Virtually all solder mask manufacturers offer matte and semi-matte formulations. In addition to mitigating glare these reduced-gloss masks arguably improve conformal coating bond, something of a bonus. So ask your board fabricator, as this should be an easy topic of conversation for them.
Robert "Bob" Lazzara
Circuit Connect, Inc.
Bob has been in PCB design and fabrication since 1976. He has held elected positions with the SMTA, is a member of the MSD Council, has served as a committee member for various IPC standards and is a Certified IPC Trainer.
Diffuse lighting is going to make the biggest difference overall. You may be able to reduce some glare by using polarized glasses, but there are two distinct limitations to them:
You may also be able to reduce reflections by changing the surfaces, for instance by specifying a semi-matte solder mask, if glossy mask Is part of the problem.
- Polarizers cancel reflections only from non-metallic surfaces. Reflections off of metals are not affected
- Polarizers only cancel reflections in one orientation; you can choose to reduce reflections off of horizontal surface or vertical surfaces, for instance, but not both
Fritz's career in electronics manufacturing has included diverse engineering roles including PWB fabrication, thick film print & fire, SMT and wave/selective solder process engineering, and electronics materials development and marketing. Fritz's educational background is in mechanical engineering with an emphasis on materials science. Design of Experiments (DoE) techniques have been an area of independent study. Fritz has published over a dozen papers at various industry conferences.
Glare from direct task lighting can be a myriad of issues. Facility Lighting, Ambient light direction, Solder Finish, Solder Mask and task lighting types ... most common, "Halo" versions, Florescent and Desk lamps.
Someways in which we have managed lighting involve the following:
These are mere considerations, above to remedy the source of your problem.
- Increase your Ambient lighting, we have a minimum of 40 ft-candles of lighting on our floor from above.
- Reduce your Natural light from side windows (if present) most commonly with blinds.
- Diffuse light on task lighting, no reflective lenses or clear glass. Use only diffused light and frosted bulb glass
- Provide Dimmer to task lighting, for settings that help operators optical preferences.
- Use non-reflective work surface and walls with flat paint. The darker work surface colors work better.
- Add a board holder to the manual process, with adjustable angle that can be fixed
- Specify Solder mask with matte finish. Generally acceptable, and worked better with conformal coated product.
- Review Solder Finish types. White Tin, ENIG and other plated options tend to glare less than HASL.
Capital Equipment Operations Manager
Specialty Coating Systems
Rodney is currently Operations manager at SCS coatings, Global Leader in Parylene and Liquid Coating equipment. Rodney applies his BS in Computer Integrated Manufacturing from Purdue University, along with 20+ years of Electronic manufacturing and Equipment Assembly, to direct the Equipment business at SCS Coatings. "We provide unique, value added coating equipment solutions for our customers". Including conformal, spin and Parylene coating expertise.