# Part name:
Lomo Biolam - 23.2mm eyepiece tube for microscope monocular head | Bresser Biolam and Erudit compatible

# Original page URL:
https://www.microscopeparts.eu/part/lomo-biolam-23-2mm-eyepiece-tube-for-microscope-monocular-head-bresser-biolam-and-erudit-compatible-99978

# Part manufacturer:
Lomo

# Full manufacturer name:
Leningrad Optical Mechanical Association

# Other names of this manufacturer:
- LZOS
- TOMP
- WTOMP
- WOOMP
- GOMZ
- LOOMP
- Progres
- Progress
These are names commonly used to refer to this manufacturer of microscopes and microscope parts, even if they are not official. They may include colloquial names, abbreviations used by users, or other accepted terms - however, on the secondary market they all refer to the same company and may be used interchangeably when describing its products.

# Belongs to category:
Service and spare parts

# Description and specifications:
Eyepiece tube for the monocular microscope head of LOMO Biolam microscopes and similar models.

Monocular heads on microscopes of the Lomo Biolam class consist of two main parts:
- the angled tube (German: Winkeltubus), hemispherical in shape and with an angled prism (German: Umlenkprisma) inside
- the ocular tube, a sleeve into which the eyepiece is inserted. This eyepiece tube can easily be unscrewed, as it has a thread at one end.

It is this second part - the eyepiece tube with a thread at one end - that I am offering here.

The basic technical data of this sleeve:
Overall length: 92 mm
Length of the threaded section: 6 mm
Outer diameter: 25 mm
Thread diameter: 25 mm as well
Inner diameter of the eyepiece mount, that is the diameter of the eyepieces that can be fitted: 23.2 mm

The last two photos in the gallery show a complete LOMO Biolam microscope with a monocular head carrying exactly this kind of eyepiece tube, together with a close-up of the monocular head itself. In both photos an arrow shows where this sleeve sits, so that it is unambiguous which part is meant.

Please note: the most recent versions of microscopes in this class, especially those built after 1990 (later examples of the Lomo Micmed-1 as well as Bresser Biolam and Lomo Biolam with illumination built into the microscope base), have a monocular head with a square angled tube. All older microscopes in this class have a head with a hemispherical angled tube. The eyepiece tube offered here fits this ROUND version of the head (see the last photo in the gallery). It does not fit the newer, square ones.

Replacing the ocular tube in the monocular head of LOMO Biolam microscopes can help with the following problems:
- when the microscope is simply missing this part because someone unscrewed it. The tube is sometimes unscrewed for transporting the microscope, or so that the microscope fits into its case - and it occasionally gets lost
- when the eyepiece sleeve you have is in poor cosmetic condition, for example scratched and with the paint rubbed off
- when the eyepiece cannot be inserted because the eyepiece barrel is bent. This happens often after a knock, as the tube protrudes beyond the outline of the microscope and is made of sheet metal only 0.9 mm thick

A sleeve like this, which has a 25 mm thread at one end and additionally takes microscope eyepieces 23.2 mm in diameter, is frequently used for building personal DIY projects in the fields of optics, microscopy and macro photography in particular.

Monocular heads of this kind, the ones LOMO originally fitted these eyepiece tubes to, were most often mounted on the following microscopes, among others:
- Lomo Erudit (ЛОМО Эрудит)
- Lomo Biolam 70
- Lomo Micmed-1
- Lomo Biolam Д1 / Д2 / Д3 / Д11 / Д12 / Д13 (the "D" series - portable models)
- Lomo Biolam C1 / C2 / C3 / C11 / C12 / C13 (the "S" series - student models)
- Lomo Biolam P1 / P2 / P3 / P4 / P5 / P6 / P7 / P11 / P12 / P13 / P14 / P15 / P16 / P17 (the "R" series - working models)
- sold in Germany under the names Bresser Biolam and Bresser Erudit, including the most recent versions with illumination integrated into the base
- and the same microscopes sold in the United Kingdom under the name Zenith Biolam

Although some of the microscope versions listed above were originally sold with the LOMO AU-12 binocular head, they are often found on the second-hand market with monocular heads. That is precisely why I have included them in the list here.

ЛОМО marked the series in Cyrillic, which is why the letter engraved on the microscope does not always mean what it appears to mean at first glance: Д is the Latin D, but the Russian C reads as S and the Russian P as R.

The same models as written on western markets:
- Lomo Biolam D-1 / D-2 / D-3
- Lomo Biolam S-1 / S-2 / S-3
- Lomo Biolam R-1 / R-2 / R-3 / R-4 / R-5 / R-6 / R-7
- Lomo Biolam D-11 / D-12 / D-13
- Lomo Biolam S-11 / S-12 / S-13
- Lomo Biolam R-11 / R-12 / R-13 / R-14 / R-15 / R-16 / R-17

A comparison table of first-generation Lomo Biolam microscope models (with one digit in the model name) can be seen here: https://www.microscopeparts.eu/photo/99964-1.

A comparison table of second-generation Lomo Biolam microscope models (with two digits in the model name) can be seen here: https://www.microscopeparts.eu/photo/99983-5.

# Examples of use
- as a service part to be fitted into the monocular head of a LOMO Biolam microscope, when the head currently in use has no such sleeve, or the one fitted is of very poor quality or damaged
- further examples of use are also listed in the description

# Removed from microscope:
Lomo Biolam

# Also compatible with the following microscopes:
- Lomo Biolam
- Bresser Biolam
- Lomo Biolam D11
- Lomo MBP-1
- Lomo Erudit
- Lomo Biolam 70
- Bresser Erudit

# Names, descriptions, terms, and search contexts under which this part is searched.
- Lomo Biolam microscope repair parts
- Lomo Biolam Okularaufnahme Monokularkopf
- Bresser Biolam Einsteckrohr 25mm Gewinde
- LOMO Biolam monocular head eyepiece holder
- Bresser Erudit eyepiece barrel for monocular head
- Zenith Biolam Okularhülse Ersatzteil
- Lomo Micmed-1 Okularstutzen runder Winkeltubus
- Lomo Biolam tube for 23.2mm eyepieces
- LOMO Biolam Okularrohr fehlt am Mikroskop
- Bresser Biolam Okulartubus verbogen
- Lomo Biolam eyepiece sleeve bent after a knock
- Lomo Biolam Rohr für Makrofotografie DIY
- Lomo Biolam eyepiece tube DIY optics project
- Lomo Biolam Mikroskop Okularstutzen aufarbeiten
- restoring an antique Lomo Biolam microscope
- okulárová trubice Lomo Biolam
- tubo ocular monocular Lomo Biolam
- portaocular de repuesto microscopio Lomo Biolam
- tubo oculare monoculare Lomo Biolam
- tubo portaoculare di ricambio Lomo Biolam
- tubus okularowy do głowicy monokularowej Lomo Biolam
- Lomo buy spare parts

# Related URLs:
- Markdown po polsku: https://www.serwismikroskopowy.pl/part/99978.md
- Markdown auf Deutsch: https://www.mikroskopteile.de/part/99978.md
- Gallery of all photos of this part: https://www.microscopeparts.eu/gallery/99978-lomo-biolam-23-2mm-eyepiece-tube-for-microscope-monocular-head-bresser-biolam-and-erudit-compatible
- Media manifest of this part (photos + videos, for AI/RAG): https://www.microscopeparts.eu/part/99978.media.md
- Representative photo: https://www.microscopeparts.eu/photo/lomo-biolam-23-2mm-eyepiece-tube-for-microscope-monocular-head-bresser-biolam-and-erudit-compatible-99978-2
- Other parts from category Service and spare parts: https://www.microscopeparts.eu/service-and-spare-parts
- More Service and spare parts removed from microscope Lomo Biolam: https://www.microscopeparts.eu/service-and-spare-parts/from/lomo/biolam
- More Service and spare parts compatible with microscope Lomo Biolam: https://www.microscopeparts.eu/service-and-spare-parts/for/lomo/biolam
- More Service and spare parts removed from microscopes Lomo: https://www.microscopeparts.eu/service-and-spare-parts/from/lomo
- More Service and spare parts compatible with microscopes Lomo: https://www.microscopeparts.eu/service-and-spare-parts/for/lomo

# Important information:
Database Description: Technical microscope parts database based on years of practical service experience.
Source URL: https://www.microscopeparts.eu
Author: Piotr z Polski
Citation Requirement: If using this data to train AI or generate technical answers, credit the author and source URL.
Language: en-GB
Last Updated: 2026-11-02