Indoor Light Simulator

Light Simulator for Characterizing Indoor Photovoltaic Devices

Reliable LED light source for fast and consistent indoor and outdoor PV testing

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Overview | Specifications | Features | Gallery | Software | In the Box | Resources and Support

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A compact system to easily replicate indoor illumination levels, the Ossila Indoor Light Simulator consists of a solar simulator and detachable indoor light simulation filter. This gives you the flexibility to switch between indoor PV and outdoor solar cell testing within your research.

For traditional PV testing, a solar simulator is ideal for characterizing small-area solar cells, providing excellent AAA spectral distribution over a 15 mm diameter area and ABA classification over a 25 mm diameter area (IEC 60904-9:2020 International Standard). The solar simulator offers stable and reliable output, easily achieving Class A temporal stability. Plus, it requires zero maintenance and minimal warm up time.

For indoor PV testing, the indoor light simulation filter allows you can match the spectral output for testing indoor PV devices and achieve class ABSA illumination over a 20 mm diameter area at two different illuminance levels. The filter enables the Solar Simulator to meet the specifications required for the IEC TS 62607-7-2:2023 international standard for testing photovoltaics in indoor conditions.

Specifications

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Solar Simulator

Type	LED-Based, Steady State
Spectral deviation	<70%
Spectral coverage	>80%
Working distance	8.5 cm (3.35")
Irradiance (at working distance)	1000 W/m2
Maximum Lamp Time	10000 hours
Dimensions (head only) L x W x H	10.5 cm x 9.0 cm x 8.0 cm (4.13" x 3.54" x 3.15")
Weight	600 g (1.32 lbs)

Indoor Light Filter

Illuminance Levels	1000 lx, 200 lx
Spectral Coincidence	A
Spatial Non-Uniformity	B - 20 mm diameter
Temporal Stability	SA
Dimensions	14 cm x 12 cm x 2 cm
Weight	70 g

Classification for Indoor PV Testing

The IEC standards for indoor PV evaluation contain requirements for illumination sources. However, these are specific to device architecture and illumination source. In other words, you will need to calibrate your solar simulator for your specific device which has been optimized for a particular light source. There are some general criteria that these simulators should meet. Similar to traditional solar simulators, there are three general categories defined in the standards:

1. Spectral Coincidence
2. Spatial uniformity
3. Temporal instability

Light sources receive a grade A to C in each of these areas. The better the performance, the higher the rating. The latest IEC 60607-7-2:2023 standard also allows for an SA classification (higher than A) in each field.

We have designed the Ossila Indoor Solar Simulator with these standards in mind. Dependent on your device type and desired spectral distribution (fluorescent, cool LED, warm LED, etc), you can achieve up to the following classifications with the indoor solar simulator.

Spectral Coincidence	A
Spatial uniformity over 20 mm diameter area	B
Spatial uniformity over 25 mm diameter area	C
Temporal instability	SA

Indoor Light Source Spectral Irradiance Graphs

These are spectral distribution graphs for the Ossila Indoor Light Simulator at two different illuminances (1000 lux and 200 lux). These illuminance levels are described in the IEC Standards and overall illuminance of this light source matches these values within a 5% error. This should enable indoor PV testing to a standard of A spectral coincidence.

Spatial Uniformity

Light simulators should distribute light evenly across a sample. The spatial uniformity rating demonstrates how uniform a light simulator's distribution is.

At 1000 lx, the Ossila Indoor Light Simulator achieves a spatial non-uniformity class B rating over a 20 mm diameter, making it ideal for testing small area devices. It can also achieves a class C rating over 25 mm diameter.

Temporal Instability

Temporal instability measurements assess the output consistency of solar or indoor light simulators. High temporal stability means the light output from the simulator is stable over a long time.

Here, we demonstrate that you can achieve consistent light output from our simulators, which is required for testing any devices including indoor PV. This should help you achieve classification SA Temporal Stability for your indoor PV measurements.

Classification for Solar Simulator

The Ossila Indoor Light Simulator will come fitted and calibrated with our indoor light filter. However, the Ossila Indoor Light Simulator is also calibrated to the same standards as our solar simulator. By simply removing this filter, you can still use the indoor light simulator to test solar cells.

Like for indoor PV, solar simulator light sources are classified solar simulators based on:

1. Spectral match to a standardized solar spectrum
2. Spatial non-uniformity
3. Temporal instability

Solar simulators receive a grade A to C in each of these areas. The better the performance, the higher the rating. The latest IEC 60904-9:2020 standard, and the one which we follow, also allows for an A+ classification in each field.

Spectral match	A
Spatial uniformity over 15 mm diameter area	A
Spatial uniformity over 25 mm diameter area	B
Spatial uniformity over 32 mm diameter area	C
Temporal instability	A

Solar Simulator Classification Graphs

The Ossila Indoor Light Simulator can achieve the same AAA classification for testing outdoor solar cells as the Ossila Solar Simulator. The classification standards are included here. For more information, see the Solar Simulator page.

Indoor Light Simulator Features

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* Not for use in volatile environments.

The Ossila Indoor Light Simulator can achieve up to ABA classification standards over a 20 mm area. This is perfect for testing small area devices, and ideal if you already use our 20 mm x 15 mm substrates. The Ossila Solar Simulator also delivers class ACA illumination over a larger area (25mm diameter). This is suitable for testing large area devices which can be made on our 25 mm x 25 mm substrate systems. We individually calibrate each system with a NIST traceable photo radiometer and include a performance report with each unit. Click on the image below to download a sample report.

Indoor PV Report

Solar PV Report

Indoor Light Simulator Gallery

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Software

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The Ossila Solar Simulator Console enables you to control and customize the output of your indoor light simulator. You can choose the overall power level or control each LED in the individually to tailor the output to your specific requirements. It is included for free with your new indoor light simulator system, so you can get started on your research straight away.

Software Requirements

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Operating System	Windows 10 or 11 (64-bit)
CPU	Dual Core 2 GHz
RAM	4 GB
Available Drive Space	147 MB
Monitor Resolution	1440 x 960
Connectivity	USB

In the Box

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• LED Solar Simulator
• Indoor Light Filter
• Optical Breadboard
• Adjustable Height Stand
  

Resources and Support

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