Knowledge Base
FAQs - Solar Simulator
What is the Solar Spectrum?
Sunlight is electromagnetic radiation from the sun across its entire spectrum, closely resembling that of a 5,800K black body. 99.9% of its energy is concentrated in the infrared, visible, and ultraviolet regions. In order of increasing wavelength, it is divided into five regions: UVC (100-280 nm), UVB (280-315 nm), UVA (315-400 nm), Visible Light (400-760 nm), and Infrared (760 nm – 1 mm)
What is Air Mass (AM)
What do AM0, AM1, and AM1.5 spectra represent?
- AM0: Means “zero atmosphere,” referring to the spectrum outside the Earth’s atmosphere, approximating 5800K blackbody radiation. Used for characterizing solar cells for space applications. Irradiance is about 1366 W/m².
- AM1: Means “one atmosphere,” referring to the spectrum when the sun is directly overhead and sunlight passes vertically through the atmosphere to sea level.
- AM1.5: Represents sunlight passing through 1.5 times the atmospheric thickness, corresponding to a solar zenith angle θ=48.2°. This is the standard condition for terrestrial photovoltaic testing.
What are AM1.5G and AM1.5D spectra?
- AM1.5D (Direct): Direct beam radiation. The component of sunlight that reaches the test plane directly after passing through the atmosphere at a 48.2° angle.
- AM1.5G (Global): Global total radiation. Includes both the direct beam radiation and all the diffuse radiation from various angles that reaches the test plane.
What is the irradiance intensity of AM1.5G and AM1.5D?
According to standard IEC 60904-3, under standard test conditions:
- The irradiance intensity for AM1.5G is 1000 W/m² (or 100 mW/cm²).
- The irradiance intensity for AM1.5D is 900 W/m² (or 90 mW/cm²).
What are 1 Sun Intensity' and the 'Solar Constant'?
- Solar Constant: The total solar irradiance received perpendicular to the sun’s rays outside the Earth’s atmosphere, approximately 1348 W/m². This intensity is referred to as ‘One Sun’ under AM0 conditions.
- 1 Sun: Commonly refers to the irradiance of 1000 W/m² under standard terrestrial test conditions (AM1.5G).
What is the standard wavelength range for the solar spectrum?
International standards ASTM and IEC define different spectral ranges. IEC 60904-9 defines two standard spectral ranges for terrestrial photovoltaics:
- Restricted Range: 400 nm to 1100 nm
- Extended Range: 300 nm to 1200 nm
What is a Solar Simulator?
According to IEC 60904-9, a solar simulator is equipment equipped with a light source whose spectral distribution approximates natural sunlight, used for determining the characteristics of photovoltaic devices. It is an artificial light source that mimics the sun’s spectrum and intensity.
What are the applications of Solar Simulators?
Applications are broad, including:
- Energy Science (Solar cell testing, Hydrogen production)
- Biotechnology (Pharmaceuticals, Cosmetics testing)
- Materials Application & Development (Photocatalysis, Material testing)
- Construction (Weathering tests, Coatings research)
- Agricultural Science (Cultivation experiments)
- Environmental Engineering
How is the performance of a Solar Simulator evaluated，and What is an AAA Solar Simulator?
According to the international standard IEC 60904-9, performance is evaluated based on three key parameters:
- Spectral Match: Conformity to the standard AM1.5 spectrum.
- Spatial Non-Uniformity: Uniformity of irradiance across the test plane.
- Temporal Instability: Stability of the output beam over time.
IEC 60904-9 classifies each of the three performance parameters into four grades: A+, A, B, C. The overall simulator class is denoted by three letters, representing the grade for Spectral Match, Non-Uniformity, and Instability in that order (e.g., CBA means Class C Spectral Match, Class B Uniformity, Class A Instability).
An AAA Solar Simulator refers to a simulator whose three key performance parameters—Spectral Match, Spatial Non-Uniformity, and Temporal Instability—all achieve the highest Class A rating.
What are the two types of Temporal Instability?
- Short-term Instability (STI):
Evaluates the fluctuation in light intensity at the moment of a single IV data point acquisition (simultaneous measurement of voltage, current, and irradiance). - Long-term Instability (LTI):
Evaluates the fluctuation in light intensity during the entire IV curve sweep.
Difference of Lamp source: Xenon & LED
- General Comparison Table
Item Xenon Lamp System LED System Spectral characteristics Continuous spectrum (very close to real sunlight) Peak-type spectrum (approximated by composition) Wavelength range Wideband (300–2500 nm) Depends on LED lineup (narrow-band, requires supplementation) Spectrum adjustment Optical adjustment / filter replacement Easy by multi-channel LED output control Temporal stability Warm-up and degradation over time Instant start, very small fluctuation, long lifetime Large-area illumination Strong: up to ~400 mm square, stable 1 SUN+ Uniformity is challenging for modules AM0 support ◎ Proven results in AM0 applications △ Difficult to compensate NIR region Maintenance Filter and lamp replacement Very little maintenance required Operating cost △ Lamp consumption & power cost ◎ Very low running cost Standard compliance IEC / ASTM / JIS mainstream method Still developing, full AM band tuning is difficult - A. Space Application (AM0 Perspective)
Aspect Xenon LED AM0 spectrum reproduction ◎ Excellent, strong in NIR continuous spectrum △ Limited LED bands make approximation difficult Peak irradiance reproduction ◎ ○ Depends on optical design Space cells (III-V, multi-junction) ◎ Industry standard △ Immature Standard compliance (ASTM E490, IEC 60904-9) ◎ Well-established △ Under research Space agencies (NASA / JAXA / ESA) Mainstream light source △ Used as supplementary source Summary
Xenon is the practical standard for AM0 qualification.
LED is used as a supplementary and small-scale experimental source.- R&D Applications (Perovskite & Tandem Cells)
Aspect Xenon LED Spectrum tuning by device type △ ◎ Independent channel control Light-induced degradation / MPP tracking ○ ◎ High stability and controllability Chopping / Pulse / PWM △ Complex optics ◎ Excellent Perovskite aging test ○ ◎ Superior temperature control Tandem cells (Si + perovskite etc.) ○ ◎ Layer-matched power tuning Summary
LED is rapidly growing in R&D. Xenon remains essential for reference-grade evaluation.
- C. Mass-Production Line Applications
Aspect Xenon LED Large-area illumination (100–400 mm) ◎ △ High cost and uniformity challenges 1 SUN output stability ◎ Proven feedback control ○ Initial investment △ ○ Lower Running cost △ ◎ Very low Maintenance △ Filters & lamps ◎ Minimal Summary
Xenon remains dominant for mass production. LED widely used for small-area cell testing.
- D.Website-ready Text (Polished Sales/Marketing Style)Advantages of Xenon Solar Simulators
Xenon solar simulators feature a continuous spectrum extremely close to natural sunlight.
They cover a wide wavelength range from 300 to 2500 nm, enabling evaluation of
everything from silicon solar cells to advanced multi-junction space cells.They also provide excellent uniformity and high irradiance over large-area illumination,
making Xenon the most trusted solution for research institutes, space applications,
and production-line certification testing.Advantages of LED Solar Simulators
LED solar simulators independently control multiple wavelength channels,
allowing flexible spectral shaping tailored to the device under test.With long lifetime, low power consumption, and superior temporal stability,
LED systems are rapidly emerging in cutting-edge research such as perovskite
and tandem-structure solar cells.
What are the core application fields for SAN-EI's solar simulators?
Laboratories
Automotive/Aerospace industries
Semiconductor material testing
PV cell manufacturing
Agriculture & Technology sectors
FAQs - UV Equiment
Does SAN-EI have a machine that I can use for adhesion of refined parts?
With our UVF serious and variety of fibers and lenses can work for that. We have experiences working with big companies and have sold thousands of our machines. Please trust and contact us.
Is it possible to provide light of specified wavelength equally to the experiment sample?
Specified wavelength transmission filter (B and Pass Filter) with either UVF series (small size, high power) or UVE series (80~300mm, equalized irradiation light) can work. Based on UV energy (mj/cm²) and irradiation diameter that customers request, output of lamp can be selected.
Can I manage and observe UV energy from several UV devices at the same time?
With UVM-MP from UVM series, it is possible. We can observe and monitor 6 devices of UV strength (mW/c‡u) with one UVM-MP at the maximum level. When relay amplifier box installs, it works even though measuring instrument and UV device are 10m far from each other.
Do you manufacture exposure devices for the silicon wafer micro machining?
We have wide experiences to make the light source of Mask aligner device for each brand. (UVE series) We try to cooperate with Aligner device companies to make proposal for custom-made. Our products can also work for the light imprinter of recent nano-imprinter. Please consult with us.
What are the core application fields for SAN-EI's UV system?
- Printing & Coatings
- Electronics
- Medical Devices
- Optics & Glass
- Automotive & Aerospace
Solutions
Perovskite Solar Cells
SAN-EI has provided numerous solar simulators and measurement-related systems to domestic and overseas research institutes and companies for many years. This experience allowed us to accumulate a wealth of know-how and technology in solar cell research and development and manufacturing.