What Is the Difference Between Integrating Sphere and Spectroradiometer?

In photometric and radiometric measurements, integrating spheres spectroradiometers is a common practice. Photometers and radiometers detect optical energy emitted by a variety of sources, including lasers, fluorescent materials, electrical discharge sources, and even the sun. The radiometer simply represents the magnitude of the source, whereas photometers measure the intensity of the source as perceived by the human eye. If you know the difference between an integrating sphere and a spectroradiometer, read on.

What is a Spectroradiometer?

A spectroradiometer is a light measuring device that can measure both the wavelength and the amplitude of light. To measure brightness, precision radiance, and chromaticity, these devices utilize light intensity calibration.

They have calibrations and optics that allow them to measure intensity, power, radiance, and irradiance in a calibrated manner. As a reference tool, this sort of equipment is frequently employed in R&D laboratories.

What is an Integrated Sphere?

An integrated sphere is a spherical-like device that is used to assess the strength of undirected light sources. It operates on the diffusion principle where light enters the sphere through microscopic holes, reflects through the sphere’s inner coating, and is dispersed evenly within. This enables flux measurement and a variety of other operations.

This is sometimes referred to as an Ulbricht sphere and is occasionally used interchangeably with a Coblentz square. Unlike the diffusive inner structure of the integrating sphere, the latter possesses a mirror-like inner structure. The most significant component in the measuring process is the sphere’s inside covering.

Key Differences between these Devices

A spectroradiometer works similarly to a radiometer, photometer, or colorimeter, except that measurements are taken spectrally, and photometric and colorimetric characteristics are calculated.

A Spectro radiometric measurement gives more precise findings than a photometer measurement for limited range emitters such as LEDs, discharge lamps, CFLs, and LCDs. Furthermore, spectral measurements are the sole technique to assess a light source’s color rendering ability.

Spectroradiometers are used in all fields of light metrology, from LED lighting and display photometry to photobiological applications such as blue light (Bilirubin) phototherapy, UVC germicidal radiometry, and UVB erythema detection.

On the other hand, an integrating sphere gathers electromagnetic radiation from a fully external source, often for flux measurement or optical attenuation. Radiation introduced in to integrating sphere hits the reflecting walls and is diffusely reflected numerous times.

The radiation is spread very evenly at the spherical walls after multiple reflections. The resultant integrated radiation level is proportional to the starting radiation level and may be easily detected using a detector.

Things to Consider

The variety of integrating spheres and spectroradiometers available in various sizes and functions makes them suitable for a wide range of purposes. When selecting this equipment, the most important element to evaluate is the maximum dimensions of the light source to be measured.

For example, bigger sources will require all use of bigger sized equipment, whilst smaller sources will require the use of smaller integrating spheres or spectroradiometers, whichever is suitable according to your need. This will significantly reduce any errors in the measurements of the sources.

In short, this was a brief introduction to the differences between the two devices. Hope this helps.

If you want to know more about integrating sphere and spectroradiometer, we suggest that you check out LISUN GROUP.