Connect and share knowledge within a single location that is structured and easy to search. Were there any interesting historical reasons for the initial choice, or was it just a product of what one particularly successful company was doing that became the de-facto standard?
There are a few competing theories for why the solder mask of PCB is commonly green. Source: Thefreelibrary.
Liquid Photo Imageable Solder Mask LPISM technology was developed in the late s and early s to to meet the new application demands placed upon solder masks by the rise in surface mount technology.
It seems that modern, green colored PCBs emerged with this technology, and the technology seems to trace back to this patent from Consequently, endeavours have been made to produce improved processes for producing a mask image of relatively high resolution for the small-conductor art.
It was therefore a relatively obvious step to use photo processes in association with UV ultra-violet sensitive photopolymers. The polymer solution they used in the patent included 3g of dye, but did not describe the color of the dye or why they used it. When developing an invention for the first time, it seems highly unlikely they would choose the dye or photopolymers because of the military's request or for ergonimic considerations, so we can rule those out.
The most plausible explanation is that it was the most accessible, inexpensive and effective materials to be used in fabrication. For whatever reason, the UV sensitive photopolymers that were effective for this invention happened to be green at the time, and this material's proliferation is most likely due to its low cost.
Alternatives do exist these days, and PCBs can be virtually any color. I know this is all speculation, and I wish I could give a more definitive answer. I've read through patents and papers and Electronic Materials and Processes Handbook , but still haven't nailed it down yet. Maybe a PCB process engineer or researcher can help us here. However the article states it's based on theories from forum posts and none are proven to be correct.
It seems mostly speculative but certainly a few and maybe all would make some sense. The green solder mask dams better than other colors, at 0. Some believe that the green color was chosen and made standard because of the military. The United States military studied PCB colors and found that green was the most effective color, especially when they tested them in adverse situations.
Because of their tests, the military decided that green printed circuit boards would be the norm. And, the pcb manufacturers who supplied circuit boards to the military had several non-military customers, too. According to research, green is the easiest color for the human eye to see. It is a mixture of red and blue. Because green exists near the middle of the color spectrum at nanometers, the primary colors that make green are easier for the human eye to perceive.
So, when looking at something small and complicated, like a PCB , choosing green makes sense. The human eye is easily strained by looking at something like a PCB. Green reduces eye strain, so employees tasked with inspecting PCBs can do it without their eyes becoming tired.
They can see all of the parts of the PCB and conduct effective manual screening. Other colors tire the eyes more frequently. Using green creates a noticeable contrast between the green of the solder mask and the traces, pads, and silk screening. Fast You will benefit from the fastest leadtimes in the UK. Friendly Your order will be dealt with promptly by a friendly and conscientious team, committed to providing a high level of service.
Exceptional You will also benefit from our exceptional 8 hour same day express service for your urgent prototypes. Experienced The knowledge gained from 30 years of experience eliminates your risk in dealing with ABL Circuits. Need help? Get in touch. We use cookies on our website to give you the most relevant experience by remembering your preferences and repeat visits.
You can view our cookie policy here. Manage consent. Green creates less eye strain and makes it easier to see every part of the PCB. Plus, line workers are now the most accustomed to green circuit boards, so they likely have an easier time quickly scanning green PCBs than they do other colors.
There is more pigmentation in the darker color solder masks blue, black, white , therefore they require a higher exposure rate. Black and white solder mask will require the highest exposure rate.
Selecting green solder mask will also allow the client to achieve tighter tolerances on their design. Depending on the situation and production process, certain colors can work just as well as green or even surpass it. Common alternative colors include:. To learn more about the PCB colors you can order from a supplier, contact us online or call
0コメント