Space solar cells are measured under AM0, the spectrum of the sun above the atmosphere: bluer and stronger than terrestrial sunlight, and reaching far into the infrared. Most space cells are multi-junction stacks whose junctions are connected in series, so the light in every junction’s band has to be right, or the weakest junction limits the cell and the efficiency number means nothing.
The deep-IR problem for LED
An LED simulator reproduces the visible and near infrared very well. Past about 1100 nm, efficient LED coverage runs out, and that is where the bottom junction of a modern 3J or 4J cell lives. Filling that band with lasers or exotic emitters turns a simulator into a custom optics project.
The Nexun Cosmo answer: a patented hybrid
- LED engine from 300 to 1100 nm: the same Avalon architecture as the rest of the Nexun line, with every band controlled independently.
- Tungsten-halogen fill from 1100 to 1900 nm: a hot filament emits genuine blackbody radiation across the deep IR, coupled to the LED engine in Cosmo’s patented design.
- Per-junction tuning: both sources are software-controlled, so each junction of a 3J or 4J cell can be set to its operating point without disturbing the others.
- Any spectrum: ASTM E490 AM0, lunar and Martian variants, or a custom mission spectrum, with no bulb swap and no optics rebuild.
- A benchtop footprint on a Nexun PRO MAX or ULTRA base, at a fraction of the cost of a flash hall.
AM0 for crystalline silicon space cells
A crystalline silicon cell does not need the deep IR beyond its own response. For silicon space cells, a standard Nexun LED simulator can be tuned to the AM0 spectrum, with the long pulses and spectral stability of the rest of the line.
When to choose Pasan instead
Our sister company Pasan has been the reference for AM0 and multi-junction measurement since 2008. Its HighLIGHT space line was developed jointly with ESA and Thales and is used by most space agencies and by large private space companies. If your results must be directly comparable with theirs, if you test full satellite panels, or if you qualify 5J devices, measure on the Pasan HighLIGHT SAT. Read Pasan’s overview of space solar cell testing.
In short
- 3J or 4J R&D, custom spectra, benchtop, lower cost: [Nexun Cosmo](/products/nexun-cosmo).
- Crystalline silicon space cells under AM0: a standard Nexun LED simulator.
- Comparability with agencies and primes, full panels, 5J: Pasan HighLIGHT SAT.
Cosmo and the Pasan systems share one calibration chain, so results on either can be correlated. Tell us about your cells and your mission spectra.
