The X-Files (created by Chris Carter – 1993–2018) arguably marked the Sci-Fi landscape forever. It is expected for a good science fiction TV show or movie. But when you become a cultural reference in various fields, I guess you can say that you made it! The X-Files made it into the super-niche ring of pocket computer collectors. Indeed, in Tunguska (S8:E4, directed by Kim Manners, written by Chris and Frank Spotnitz), we make the acquaintance of the Black Oil, an alien virus that laid dormant in a meteorite for a while. In this episode, Dana Scully (Gillian Anderson) gets infected by the virus, and Fox Mulder (David Duchovny) gets very close to the same faith in an old-school Russian gulag – where he was lured by Alex Krycek (Nicholas Lea).
Ok, but how is this related to pocket computers? Well, as I mentioned it here a few years ago, early Sharp made LCDs don’t age well (the Yellow as well as the Grey ones). A euphemism for die on you. The symptom is similar to the X-Files’ black oil: black spots crawls into the display from the edges. It always ends the same way: the LDC turns completely black, rendered unreadable. Logically, we often call this phenomenon the black oil.
For years, we suspected a chemical root cause. It was thought that a bad seal and oxidation are causing these stains. I am planning to replace the dying LCD of my Sharp PC-1211 pocket computer with a modern replacement soon, so I decided to use my microscope to have a closer look. I attached several pictures and videos for your attention (note, I also uploaded to YouTube the raw videos). What I found very interesting is that it seems that the issue could also be mechanical related (tear and wear). Applying the polarizer – which allows us to see the liquid crystal leakage – long vertical lines are visible, almost like fatigue fracture lines.
Once I replaced the screen of my computer, I will dig deeper, literally. Note that I’ve contacted Sharp and didn’t obtain an answer. Every time I’ve discussed with LCD experts, after the usual, why do you even care, they all pointed toward a chemical issue in the process. One day, we’ll know more about the black oil. The truth is out there…
I picked somewhere (don’t ask me where and when) that the displays for the PC 12111 (AKA TRS-80 PC-1) were not genuinely by Sharp but came from a third party supplier, possibly from somewhere in South-East Asia outside of Japan. Therefore, the problem is rather unique to this single machine. – Mind that this is only hearsay and may be wrong all together.
However, if true and the displays came from some cheap fab, there’s also the possibility of a biological contamination, especially mold (always a problem in that climate and with film-like surfaces), which might take opportunity of any mechanical unevenness. At least, it doesn’t seem to be about moisture or simple delamination. – I’m curious what you’ll be able to find out or what you may have to add to the riddle.
That’s good new info Norbert, thank you for sharing. It is the first time I heard the biological contamination possible cause (and the 3rd party manufacturer). Let’s see if I can find any trace or marking that could confirm the non-sharp origin of the part). I am looking forward to replacing the LCD with a new one, maybe in a couple of weeks, I’ll keep you updated.
I guess, the LCD is one from Robert Baruch?
Regarding a possible contamination, this is really just me putting two unrelated pieces together, the unconfirmed memory of hearing/reading about there having been a third party source on the one hand, and on the other hand that I just recently learned that mold is some of a problem SE Asia (often just a thin, transparent whitish film). – If Sharp had actually contracted out the display manufacturing, but pulled out immediately and didn’t continue this for any subsequent models, was there a problem with manufacturing standards? If it isn’t about air, moisture, or the seals, which all seem to be ruled out as a probable cause, what might be the problem? In what direction haven’t we thought yet?
TLDR-version: Totally unfounded idea. 🙂
Yes, it is one of his. He also has a replacement for the PC-3, which is really cool as I started seeing those having the same issue. I hear you about the hypothesis. I guess that at some point we will find out. Now I am just looking for a long WE to have some serious time to focus on the replacement 🙂