"Auto-zoom" is written on my Zuiko 35~70mm lens, is this a name of some lens technology?
Your lens dates back to a time when some lenses were still completely manual, and the aperture had to be manually closed for stop down metering.
Your zoom lens has a more modern feature that allowed for wide open metering and then the lens would automatically stop down to the desired aperture just as the photo was taken. By the 1970’s most lenses had this feature and they were called “auto” lenses.
That’s why it is called “Auto-Zoom”.
"Auto" is a descriptor that appears to have been overused because it sounded advanced and futuristic. Now that we are in the future, it refers to outdated technologies that don't seem very automatic. For instance, since the term auto-mobile has already been taken, we're stuck calling autonomous vehicles "self-driving cars".
While it would be reasonable to think the phrase refers to a single feature, like the ability to automatically zoom the lens, "auto-zoom" refers to two separate features:
- Auto refers to the aperture control, as Mike Sowsun describes.
- Zoom refers to the ability to change focal length.