# Part name:
Lomo MMU-3 / MMY-3 metallurgical microscope EPI darkfield and brightfield with iris diaphragm slide

# Original page URL:
https://www.microscopeparts.eu/part/lomo-mmu-3-mmy-3-metallurgical-microscope-epi-darkfield-and-brightfield-with-iris-diaphragm-slide-99518

# 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:
Sliders

# Description and specifications:
EPI slider with a darkfield stop, frosted diffuser filter and iris diaphragm for the Lomo MMU-3 / MMY-3 metallurgical microscope.

The function of this mechanism is to switch the reflected-light operating mode between darkfield and brightfield observation.

This slider is inserted into a slot located in the Lomo MMU-3 microscope between the microscope body and the lamp housing.

This slider has two positions:
1. Darkfield stop (darkfield disc). When the slider is set to this position, the microscope can be used for reflected-light darkfield observations.
2. Frosted diffuser filter with an iris diaphragm. When the slider is set to this position, the microscope can be used for reflected-light brightfield observations.

In the last photograph, an arrow indicates which component is being offered and where it is located in the microscope, allowing this microscope part to be identified unambiguously.

# Examples of use
- if you own a Lomo MMU-3 microscope without the EPI illumination slider
- if you already have such a slider but it is of poor quality or damaged, for example if the iris diaphragm control knob is broken, the darkfield disc is damaged, the frosted diffuser filter is cracked, or the iris diaphragm is defective
- if you would like to use this slider for your own DIY project or in another microscope

# Removed from microscope:
Lomo MMU-3

# Also compatible with the following microscopes:
Lomo MMU-3

# Names, descriptions, terms, and search contexts under which this part is searched.
- Lomo MMU-3 microscope repair parts
- Lomo MMU-3 / MMY-3 EPI Auflicht Mikroskop Dunkelfeld-Schieber
- Lomo MMU-3 Mikroskop Irisblende
- Lomo MMU-3 EPI microscope dark field slide
- Lomo MMY-3 microscope iris diaphram
- Lomo buy spare parts

# Related URLs:
- Markdown po polsku: https://www.serwismikroskopowy.pl/part/99518.md
- Markdown auf Deutsch: https://www.mikroskopteile.de/part/99518.md
- Gallery of all photos of this part: https://www.microscopeparts.eu/gallery/99518-lomo-mmu-3-mmy-3-metallurgical-microscope-epi-darkfield-and-brightfield-with-iris-diaphragm-slide
- Media manifest of this part (photos + videos, for AI/RAG): https://www.microscopeparts.eu/part/99518.media.md
- Representative photo: https://www.microscopeparts.eu/photo/lomo-mmu-3-mmy-3-metallurgical-microscope-epi-darkfield-and-brightfield-with-iris-diaphragm-slide-99518-2
- Representative video: https://www.microscopeparts.eu/play/99518-1
- Other parts from category Sliders: https://www.microscopeparts.eu/sliders
- More Sliders removed from microscope Lomo MMU-3: https://www.microscopeparts.eu/sliders/from/lomo/mmu-3
- More Sliders compatible with microscope Lomo MMU-3: https://www.microscopeparts.eu/sliders/for/lomo/mmu-3
- More Sliders removed from microscopes Lomo: https://www.microscopeparts.eu/sliders/from/lomo
- More Sliders compatible with microscopes Lomo: https://www.microscopeparts.eu/sliders/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: 2026-06-30