This is description of this part:
Eyepiece tube with a 23.2 mm seat diameter and a diopter adjustment ring, for the heads used on Olympus BH-2 / IMT-2 microscopes
This is a tube with a diopter adjustment ring fitted, which lets you correct the refractive error of one eye and focus the image properly. It is mounted on the left side of the microscope head, and without certain DIY modifications it cannot be moved to the right side.
This particular tube was removed from an Olympus BH2-BI30 binocular head, but it should also fit, among others, the following microscope heads with tubes for eyepieces of 23.2 mm diameter:
- Olympus BH2-BI30
- Olympus BH2-TR30
- Olympus BH2-TBI
- Olympus BH2-TTR
- Olympus BH2-TET
Before you decide to use it to repair a head other than the one it was removed from, I recommend checking it first with specialists on forums or groups devoted to Olympus microscopes.
This tube with diopter adjustment is not a spare part for the microscope itself. It is a repair part for an Olympus microscope head - and that head can sit on various microscopes, even on instruments from manufacturers other than Olympus. The most important microscopes this head is most often used with are listed in the "compatibility" section, but this is by no means a complete list.
The irreplaceable Carl Hunsinger has written an excellent service manual for the BH2-BI30 microscope head (https://www.alanwood.net/downloads/olympus-bh2-bi30-binocular-head-repair.pdf) and for the BH2-TR30 (https://www.alanwood.net/downloads/olympus-bh2-tr30-trinocular-head-repair-manual.pdf).
Here are the microscope models in which the heads this tube fits are most often used:
- Olympus BH-2 BHS
- Olympus BH-2 BHT
- Olympus BH-2 BHTU
- Olympus IMT-2
A note on the eyepiece tube diameter: the mounting diameter for the eyepieces is 23.2 mm, but some sources state 23 mm or 23.5 mm - that is a rounded measurement, and it is still one and the same tube.
What is this part needed for?
- very often this tube is dented and an eyepiece cannot be inserted
- very often the diopter adjustment ring becomes damaged and does not function
- if you need a tube with precise worm adjustment for your own DIY purposes
