What is the blondel unit used for?

The blondel is an obsolete photometric unit once used to measure luminance, commonly found in early 20th-century lighting literature.

Why does this conversion focus on 555 nm?

555 nm corresponds to the photopic peak sensitivity of the human eye, making it key for matching radiometric spectral radiance with perceived brightness.

Can I use this conversion for modern luminance measurements?

Since blondel is outdated, the conversion is mainly suitable for interpreting historical data rather than direct application to contemporary measurements.

How to Convert from Blondel to Watt/sq. cm/steradian (at 555 nm)?

Convert luminance measurements from the historical blondel unit to the radiometric spectral radiance expressed in watt per square centimeter per steradian at 555 nm using our specialized online converter.

Blondel

Watt/sq. cm/steradian (at 555 nm)

Please check your input. It must be a valid numeric value.

Blondel to Watt/sq. cm/steradian (at 555 nm) Conversion Table

Blondel	Watt/sq. cm/steradian (at 555 nm)

Custom Unit Conversion Table Generator – Instant Printable Conversion Tables

Start Value

Enter the starting number (positive decimal or integer ≥ 0). Example: 0.1, 1, 5.

End Value

Enter the ending number (positive decimal or integer > Start Value). Example: 10, 50, 100.

Interval

Enter the step size (positive decimal > 0 and < End Value – Start Value). Example: 1.0, 2.5.

Blondel to Watt/sq. cm/steradian (at 555 nm) Conversion Table
Blondel	Watt/sq. cm/steradian (at 555 nm)

Explore More Luminance Units Converter

What Is This Tool?

This tool enables the conversion of luminance values from the obsolete blondel unit to the radiometric unit watt per square centimeter per steradian at 555 nanometers. It assists users in translating historic photometric units into modern radiometric measures centered around the photopic peak of human vision.

How to Use This Tool?

Enter the luminance value in blondel that you wish to convert.
Select blondel as the source unit and watt/sq. cm/steradian (at 555 nm) as the target unit.
Initiate the conversion process to receive the equivalent value in the radiometric unit.

Key Features

Converts from the historic blondel luminance unit to watt/sq. cm/steradian at 555 nm.
Supports conversion of data relevant to lighting engineering, vision research, and optical calibration.
Focuses on measurements aligned with the peak photopic wavelength important for human visual sensitivity.
Provides accurate translation of early 20th-century photometric data to modern radiometric standards.

Examples

2 blondel converts to approximately 9.3209337096278e-8 watt/sq. cm/steradian (at 555 nm).
0.5 blondel converts to approximately 2.33023342740695e-8 watt/sq. cm/steradian (at 555 nm).

Common Use Cases

Interpreting historical photometric records for comparison with current measurements.
Calibrating instruments and optical systems used in vision science at the 555 nm wavelength.
Supporting research that requires aligning spectral radiance with photometric luminance distributions.

Tips & Best Practices

Always double-check units before conversion to ensure accuracy in your calculations.
Use this conversion when working specifically with data related to the 555 nm wavelength for meaningful results.
Be cautious relating radiometric units directly to human brightness perception as they measure different physical concepts.

Limitations

The blondel is outdated, so this conversion mainly applies to legacy data and not current measurements.
The conversion is specific to a wavelength of 555 nm and may not reflect accurate values at other wavelengths.
Radiometric and photometric units measure fundamentally different quantities, so consider their differences when interpreting results.

Frequently Asked Questions

What is the blondel unit used for?: The blondel is an obsolete photometric unit once used to measure luminance, commonly found in early 20th-century lighting literature.
Why does this conversion focus on 555 nm?: 555 nm corresponds to the photopic peak sensitivity of the human eye, making it key for matching radiometric spectral radiance with perceived brightness.
Can I use this conversion for modern luminance measurements?: Since blondel is outdated, the conversion is mainly suitable for interpreting historical data rather than direct application to contemporary measurements.

Key Terminology

Blondel: An obsolete unit of luminance measuring luminous intensity per unit area, named after André Blondel.
Watt/sq. cm/steradian (at 555 nm): A radiometric unit measuring spectral radiance at the photopic peak wavelength of 555 nm, expressed as radiant power per square centimeter per steradian.
Photopic peak: The wavelength, approximately 555 nm, at which the human eye has maximum sensitivity under well-lit conditions.

Quick Knowledge Check

What is blondel primarily used to measure?

Radiant power

Luminance

Solid angle

At what wavelength is the conversion to watt/sq. cm/steradian specified?

555 nm

450 nm

700 nm

Why is the conversion from blondel to watt/sq. cm/steradian important?

To relate legacy photometric data to current radiometric standards

To measure temperature accurately

To calculate area of light sources

Share Us

Similar Calculators

Online Temperature Interval Units Converter Online Temperature Units Converter Online Heat Flux Density Units Converter Online Volume Dry Units Converter Online Heat Density Units Converter