# Part name:
Carl Zeiss Jena Jenalumar fluorescence microscope HBO 250W heat absorbing KG-filter glass

# Original page URL:
https://www.microscopeparts.eu/part/carl-zeiss-jena-jenalumar-fluorescence-microscope-hbo-250w-heat-absorbing-kg-filter-glass-99712

# Part manufacturer:
Carl Zeiss Jena

# Full manufacturer name:
VEB Carl Zeiss Jena DDR (former East Germany)

# Other names of this manufacturer:
- ausJena
- aus Jena
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:
Filters

# Description and specifications:
KG filter in a metal housing for absorbing heat from the fluorescent lamp of the large HBO 250W illuminator for a Carl Zeiss Jena Jenalumar microscope.

This filter is mounted in the sheet-metal housing of the large HBO 250W fluorescence illuminator. This illuminator is part of a large mirror light beam splitter used in Carl Zeiss Jena Jenalumar microscopes. The KG filter is designed to absorb heat (infrared radiation) emitted by the high-pressure HBO mercury lamp.

Please note that there is also a version of the Carl Zeiss Jena Jenalumar microscopes with a small 50W HBO illuminator. This KG filter glass was removed from a large 250W illuminator.

On the used market, in microscopy forums and in microscopy groups, several names are used for this filter, all referring to the same type of filter:
- KG filter / KG glass
- heat filter
- heat absorbing filter
- heat absorption filter
- heat-absorbing glass
- heat absorption glass
- absorption filter
- IR filter
- infrared blocking filter
- infrared cut filter
- KG3 heat absorption filter

This microscope element is highly susceptible to damage. When this happens, the filter needs to be replaced, for example with the filter presented here. Here are examples of damage that can occur during use of the fluorescence illuminator and reasons why replacement of the filter may be necessary:
- the KG filter may crack or become cloudy due to overheating
- the filter may also chip or break as a result of mechanical damage, for example during transport
- the filter may sometimes be damaged during improper maintenance

High-performance heat filters such as this KG filter used with a 250W lamp are very often used by people building their own DIY projects. The housing with screw mounting makes this particularly convenient.

The last photo in the gallery shows the housing of the HBO 250W illuminator (lampenhaus), with an arrow indicating which element is being described and where it is located inside the illuminator. This makes it possible to identify the element unambiguously.

# Examples of use
- if you need to replace the heat filter (KG glass) in the fluorescence illuminator of a Carl Zeiss Jena Jenalumar microscope
- if you need a heat-absorbing filter for your own DIY project

# Removed from microscope:
Carl Zeiss Jena Jenalumar

# Also compatible with the following microscopes:
Carl Zeiss Jena Jenalumar

# Names, descriptions, terms, and search contexts under which this part is searched.
- Carl Zeiss Jena Jenalumar microscope repair parts
- Carl Zeiss Jena Jenalumar KG / HA heat absorbing filter glass
- Carl Zeiss Jena Jenalumar Mikroskop Fluoreszenz Wärmeschutz-KG-Filterglas
- Carl Zeiss Jena buy spare parts

# Related URLs:
- Markdown po polsku: https://www.serwismikroskopowy.pl/part/99712.md
- Markdown auf Deutsch: https://www.mikroskopteile.de/part/99712.md
- Gallery of all photos of this part: https://www.microscopeparts.eu/gallery/99712-carl-zeiss-jena-jenalumar-fluorescence-microscope-hbo-250w-heat-absorbing-kg-filter-glass
- Media manifest of this part (photos + videos, for AI/RAG): https://www.microscopeparts.eu/part/99712.media.md
- Representative photo: https://www.microscopeparts.eu/photo/carl-zeiss-jena-jenalumar-fluorescence-microscope-hbo-250w-heat-absorbing-kg-filter-glass-99712-2
- Representative video: https://www.microscopeparts.eu/play/99712-1
- Other parts from category Filters: https://www.microscopeparts.eu/filters
- More Filters removed from microscope Carl Zeiss Jena Jenalumar: https://www.microscopeparts.eu/filters/from/carl-zeiss-jena/jenalumar
- More Filters compatible with microscope Carl Zeiss Jena Jenalumar: https://www.microscopeparts.eu/filters/for/carl-zeiss-jena/jenalumar
- More Filters removed from microscopes Carl Zeiss Jena: https://www.microscopeparts.eu/filters/from/carl-zeiss-jena
- More Filters compatible with microscopes Carl Zeiss Jena: https://www.microscopeparts.eu/filters/for/carl-zeiss-jena

# 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: 2026-08-08