Lamps

Buying guide

What a lamp has to match before it fits

The first thing to settle is not the lamp but the instrument it serves, because a laboratory light source is a consumable tied to one piece of equipment. A deuterium lamp outputs a continuum in the ultraviolet that a spectrophotometer reads below roughly 350 nanometres; a tungsten-halogen lamp covers the visible and near-infrared above it. Many instruments run both and switch between them at a crossover wavelength. Buy the wrong spectral output and the instrument will not calibrate, however well the lamp works on its own. So the controlling specification is the emission range the instrument was built around, and after that the fit: base type, socket, reflector geometry and the electrical rating the power supply expects. A lamp is a drop-in part only when all of those agree.

With the spectral match established, condition becomes the question on a used light source, and it behaves differently from condition on most used equipment. Lamps age in service. A deuterium source has a rated life measured in hundreds or low thousands of hours, and its ultraviolet output drops steadily across that life even while it still lights. So the hours already burned matter more than cosmetic state. On a used listing, ask for the recorded operating hours, and for an arc or halogen unit check whether the envelope is clear or clouded, since deposition on the glass attenuates output before the lamp fails outright. A used lamp at low hours is genuinely useful; a used lamp near the end of its rated life is a short-term stopgap, and the price should reflect which one it is. Where a listing carries no hour figure, the individual seller is the place to confirm it, and warranty on Questpair is arranged in consultation for the specific listing.

Price then sorts the category into its two halves. At the low end sit replacement bulbs and simple halogen sources, and a modest budget covers those; what a basic lamp costs here starts at EUR 5. At the high end sit complete arc-lamp housings, laser-driven light sources and specialised ultraviolet systems, which carry the EUR 11.662 figure. The average listing price of EUR 592 sits well below the midpoint, which tells you the catalogue is weighted toward the affordable replacement end rather than the instrument-grade assemblies. The brands that occupy the range are Various, Olympus, Agilent, Nikon, UVP, a mix that spans microscopy illumination and spectroscopy sources. Used and refurbished units listed for sale are priced below equivalent new ones, so where the spectral match and the hours check out, the used half of the catalogue is where the value sits.

Types of Lamps

Which lamp types are listed here?

Among the listings that specify a type, the catalogue splits into a handful of distinct technologies. Halogen lamps are tungsten-filament sources that emit a smooth continuum across the visible and into the near-infrared; they are the standard visible-range source in absorbance spectrophotometry and the common illuminator in brightfield microscopy. Deuterium lamps are gas-discharge sources whose output is a continuum in the ultraviolet, below the point where halogen falls away, which makes the two a matched pair inside a dual-source spectrophotometer. Ultraviolet lamps form a separate group built for direct action rather than measurement: the short and medium wavelengths they emit are what a transilluminator uses to visualise stained nucleic-acid gels and what a cabinet uses for surface decontamination. Alongside these sit general light sources that do not name a technology, and a smaller set of lamps listed as electrophysiology equipment or as a microscope accessory, where the lamp is one part of a larger imaging or recording setup.

The field work these sources do is concentrated in the life sciences. Deuterium and halogen lamps feed the ultraviolet-visible spectroscopy behind protein quantification and nucleic-acid concentration measurement, routine steps in molecular biology and protein purification. Ultraviolet transilluminator lamps are the readout stage of gel electrophoresis, the point where a DNA or RNA band becomes visible, and the same short-wavelength emission does surface sterilisation and sterilization in cell culture and microbiology work. Microscope illumination lamps and the arc sources among them also underpin fluorescence and cell imaging, where a defined excitation wavelength drives the whole technique. Lamps are also used for photostability testing and for curing in sample preparation.

The brands behind the lamp listings

The listings are led by Various, Olympus, Agilent, Nikon, UVP. The prominence of a generic "Various" entry reflects the nature of the category: a large share of lamps are replacement bulbs sold against a part number rather than a brand, which makes them straightforward to cross-reference once you have the instrument's specification. The named optical makers, the microscopy and analytical-instrument houses among them, matter more for traceability: a lamp carried under a recognised brand is easier to match to a documented spectral output and a stated rated life, and spare envelopes for those lines are easier to find. For a buyer that means a branded source is simpler to compare like for like, while a generic replacement is usually the cheaper route to the same bulb.

What a used lamp costs here

Condition is weighted toward the second-hand end, with 73 percent of the listings used. Prices run from EUR 5 to EUR 11.662, a spread that covers everything from a single replacement bulb to a complete illumination assembly, and the average of EUR 592 shows where the bulk of the catalogue sits. Used and refurbished lamps are listed below new prices. Where a listing does not state the operating hours already burned, the seller is the place to confirm them, and a warranty can be arranged in consultation for the specific listing.