No, that's not it. Sun Microsystems had optical mice too, back in the early 90s, on their SPARCstations.
The difference was that the early optical mice required a special mousepad for them to work. I think they just used some photodiodes and looked at the reflections from the mousepad, which had a pattern built in. The optical mouse starting with MS's worked in a different way, using an actual camera to track movement, so you could use them on almost any surface.
@magduf has the correct answer. The Sun optical mouse used dual photodiodes and had two grids in the mousepad. One blue, one red. The filters on the photo diodes allowed one to see both x & y grid lines and the other to see only the red stripes. Then based on their signalling you could extract a motion vector. The upside was no ball to pick up dirt and clog sensors, the downside was you needed the mousepad with the lines etched on it. You would also get less reliable results if the mouse pad was not in the expected orientation with the mouse.
Still I really enjoyed that mouse. It had excellent tactile feedback on the buttons as well.
It was a single IR LED and four sensors as I recall. They had some Sun workstations (used mostly for circuit simulations) in mid-90's at the university where my mother used to work. I was in the middle school at the time and very interested in anything electronics. Still am. Blue LEDs went mainstream few years later.
The Xerox Star / Viewpoint mice used cheap paper mouse pads with a black and white stipple texture, that you could print out on a laser printer or photocopy.
But you could not Xerox them, because Xerox is not a verb!!!
The mice released with the Xerox Star 8010
workstation and its successors, like the 6085,
all had 2 buttons, despite the earlier research
mice having three. This was to reduce
confusion. They didn’t go to 1 button like
Apple, however because their studies showed
that any reduced confusion came at the
expense of added selection errors. (Johnson,
Roberts, Verplank, Smith, Irby, Beard &
Mackey, 1989).
The Mouse Systems M1 Optical Mouse (1982)
This was the first commercially available optical mouse. Like most mice at the time, it had three buttons. Unlike today’s optical mice, the M1 needed a glass pad for optical sensing.
1981 Optical Mouse. Independently developed by Steven Kirsch, Mouse Systems and Richard A. Lyon.
The optical mouse avoided the problem of dust and dirt accumulating in the mechanisms of mechanical mice. Kirsch's mouse was commercialized by his company, Mouse Systems in 1982 (upper image to the right). A mouse based on Lyon's technology was incorporated into Xerox's 6085 "Viewpoint" workstation,which replaced the 8010 Star workstation in 1985 (lower image to the right). Unlike today’s optical mice, both of these early designs required a special mouse pad with a pattern on it that the optics used to track movement. The Mouse System's pad, seen in the first image to the right, was made of glass, while Lyon's, seen in the second image to the right, was made of paper (and hence one could make a replacement using a laser printer). You can print out your own copy of Lyon's paper pad from here.
Lyon, Richard. Imaging Array. US Patent 4521773, Filed Aug 28, 1981; Issued June 4, 1985.
Kirsch, Steven T. Electro-Optical Mouse. US Patent 4364035. Filed June 15, 1981; Issued: Dec. 14, 1982.
Johnson, J., Roberts, T.L., Verplank, W., Smith, D.C., Irby, C.H., Beard, M., Mackey, K. (1989). The Xerox Star: A Retrospective, IEEE Computer, 22 (9), 11 – 26.
Product brochure for Xerox 6085 Viewpoint workstation (1985).
In my past experience the Sun optical mousepads worked OK in single user environments, where people kept the pads undamaged and clean. Generally, in 1993 if you worked for a university or company that cared to put a $5000 (in 1993 dollars!) computer on your desk, you would treat everything associated with it with care.
They worked considerably less well in university shared computer lab environments where the pads were subject to more wear and tear.
I used those three button optical SPARC mice, and the bigger issue than the fact that you needed a special mousepad, was that the pad had to stay properly oriented. If the pad was rotated slightly, your mouse would go in strange directions.
Also, in our CS lab anyway, theft of the shiny mouse pads had evidently been an issue in the past, and they were often glued or otherwise attached permanently to the desks.
But why? And who? No student back then (early 90s) could even dream of affording a SparcStation, which were the only workstations which used the mouse that needed the shiny mats.
We had various types of Sun machines in the labs, from the IPX and 5, up to dual processor 20s, and they needed an (expensive, maybe 200Mb) SCSI disk to boot from. Video was to a chunky high resolution (i recall OpenLook on 1152x900 grayscale was awesome, or the expensive option, 1280x1024 colour) monitor with RGB plus sync input using that weird 13W3 socket with the wee coax connectors inside. For networking you had to embrace the world of AUI media converters and so forth, which was just annoying. Anyway, all that stuff would have cost essentially the same as a nice Mercedes or a suburban house...
Maybe people used the muse mats as bird scarers? Perhaps they dropped too much LSD and just stared at the shiny pattern? Stealth teams of research assistants might be sent to fetch replacements for their professor's workstation, after running out of funding, but needing a new one having used his as a coffee mat and broken it? Or I suppose they could have been stolen by accident, not knowing what they were, by someone who was blinded by staring at the little laser under the mouse...
> The difference was that the early optical mice required a special mousepad for them to work
Yeah, the article mentions this too.
Why was this such a big deal? Just include the pad with the mouse. Using a pad is nice anyway. It's not like you'd be carrying the mouse around with you, given that laptops weren't much of a thing yet.
The difference was that the early optical mice required a special mousepad for them to work. I think they just used some photodiodes and looked at the reflections from the mousepad, which had a pattern built in. The optical mouse starting with MS's worked in a different way, using an actual camera to track movement, so you could use them on almost any surface.