Getting old, so increasingly rely upon a hand magnifier, especially if have to poke around in laptops/PCs/tablets etc.
Device is illuminated, and the bulb has now failed.
Superficially, it is just a screw-in 3V torchbulb.
But it has a front protrusion, which I guess is a sort of lens incorporated into the glass envelope, and in this case, actually protrudes through the casing of device adjacent to magnifying lens, so illuminating the object being observed.
Quick deco on eBay. Found nowt!
Not even sure what would be correct name for such a bulb: thought perhaps pre-focused??
Anyone know what would be correct search term to find such a bulb?