Description
Bausch & Lomb 31-33-26 Microscope Illuminator 100W 115V Projection Light PG-26
This is a vintage Bausch & Lomb Type 31-33-26 microscope illuminator — also identified in original B&L literature as the Model PG-26 — a high-intensity projection light source designed for compound microscopy. It uses a 100-watt, 115V concentrated filament clear lamp and is built around a large-aperture condenser that delivers full field illumination suitable for photomicrography and visual observation in both black-and-white and color. The unit has been tested at our facility and is in working order.
Specifications & What's Included
- Brand: Bausch & Lomb Optical Co., Rochester, NY, USA
- Type / Model Number: 31-33-26 (PG-26 series)
- Max. Lamp Watts: 100W each
- Voltage: 115V
- Current: 9A
- Frequency: 50–60 Hz
- Lamp type: 100W, 115V concentrated filament, clear (not included)
- Illumination method: Koehler-type / concentrated filament projection
- Large-aperture condenser with multi-element lens assembly
- Lamp socket with rack-and-pinion focusing mechanism (lamp position adjustable)
- Side-mounted focus/position adjustment knob
- Top ventilation slots for heat dissipation
- CSA approved (CSA App. No. on nameplate)
- Cast metal housing, olive-green finish, freestanding benchtop form factor
- Original two-prong power cord attached
- No lamp included
Applications
The Bausch & Lomb PG-26 / 31-33-26 illuminator is a standalone light source made to attach to or work alongside Bausch & Lomb compound microscopes, providing the high-intensity, controllable illumination that critical microscopy work requires. It was designed specifically to support Koehler illumination — the gold-standard technique in optical microscopy where the lamp filament is focused out of the image plane, producing even, glare-free field illumination — making it well-suited to photomicrography in both black-and-white and color. The lamp socket's rack-and-pinion focus mechanism allows the filament to be positioned anywhere from infinity down to approximately 6 inches in front of the illuminator, giving the user precise control over the illumination geometry. This type of instrument dates from the mid-twentieth century era of American precision optical manufacturing, when Bausch & Lomb of Rochester, New York was one of the foremost producers of scientific optics and microscopy equipment in the world. Units like this remain useful today for anyone maintaining or restoring a period-correct Bausch & Lomb microscope, for laboratory historical collections, or as a practical vintage light source for general optical bench work. Replacement 100W 115V concentrated filament lamps are still readily available.
This Bausch & Lomb 31-33-26 Microscope Illuminator has been tested and is in working order — it powers on and projects light as designed, as shown in the photos. The cast metal housing shows the wear you'd expect from a vintage scientific instrument: the olive-green finish has scuffs, scratches, and surface dulling across the body, with some more noticeable marks on the front and top. The lens assembly and condenser appear intact with no visible cracks. The original two-prong power cord is present and shows age-related stiffening, with a patina on the brass prongs. The focus/positioning knob on the side turns smoothly. No lamp is included — the unit takes a standard 100W 115V concentrated filament clear lamp. Please view our photo set and contact us if you have any questions.
Warranty Information
Additional Information
Brand: |
Bausch & Lomb |
Model: |
31-33-26 |
MPN: |
31-33-26 |
Type: |
Microscope Illuminator / Projection Light Source |
SKU: |
42216 |
Wattage: |
100W (Max. Lamp Watts Each) |
Voltage: |
115V |
Current Rating: |
9A |
Frequency: |
50-60 Hz |
Lamp Type: |
100W 115V Concentrated Filament (Clear) |
Illumination Method: |
Koehler / Concentrated Filament Projection |
Series / Sub-Model: |
PG-26 |
Application: |
Microscopy — photomicrography, visual observation |
Compatible With: |
Bausch & Lomb compound microscopes |
Country/Region of Manufacture: |
United States |
Manufacturer Location: |
Rochester, NY, USA |
Condition: |
Used – Inspected and Tested |
Seller Notes: |
Unit only; includes attached power cord. Tested and in working order. |
CSA Approval: |
Yes (CSA App. No. listed on nameplate) |
Form Factor: |
Benchtop / Freestanding |
Condition Notes: |
Bausch & Lomb 31-33-26 microscope illuminator. Tested and in working order — powers on and projects light. Housing shows age-related wear and surface scuffs. Original power cord present. No lamp included. |
