Essentials of Photometry and Colorimetry (PH143-21-0)

SynopsisThe past few decades witnessed a rapid growth in the optoelectronic industry with an extensive proliferation of optoelectronic components and systems in the industry. Along with this rapid growth it is not unusual to find engineers, who were not trained in the discipline of optoelectronics, getting involved in the development and manufacturing of optoelectronics components and systems such as LEDs, IRLEDs, optical sensors and detectors and related systems.

In other developments, customers of consumer goods have become more and more sophisticated and discerning in their taste and the science of color measurement and color reproduction has become increasingly important to engineers involved in making products such as high definition LCD TVs, textiles, paints and in the printing and advertisement industries.

Photometry is the science of light measurement and colorimetry is the science of measuring colors. The human perception of brightness and color are both physiological responses that are not easily reproduced by man-made sensors, and it took many decades of refinement to arrive at the current state of precision in color and light measurements.

It is essential that engineers and personnel involved in products with specifications in photometric and colorimetric quantities have a firm grasp of the fundamentals of such quantities including its concepts and measurement techniques.

This course is developed to provide a better understanding of the field of photometry and colorimetry to fill the needs of engineers involved in research, product development, manufacturing, technical and customer support of their products with specifications related to photometric and colorimetric quantities.

Course Highlight
This course comprises of two sections i.e. photometry and colorimetry. In the section on photometry, it starts by introducing the basic and derived units typically used in light measurements including luminous intensity, flux, luminance and illuminance as well as the relationship between photometric and radiometric quantities. In addition, the participants are introduced to the measurement methods for these photometric quantities. In the section on colorimetry, among others, the concepts of dominant wavelength, color coordinates, correlated color temperatures and color discrimination are introduced. Later, the participants are taken through the computation aspects of color mixing. Also included is an introduction to color filters and filtering.

What previous participants say about this course
Answers to the question 'what did you like most about the course'

• "Calculation and knowledge sharing instructor" - 18 Feb 08
• "The photometry defination and measurement units" - 18 Feb 08
• "To learn & understand the concepts that are not available in textbooks in tertiary education" - 1 Jul 08
• "Mixing colour" - 1 Jul 08
• "Understand how photometry measurement and colorimetry mixing" - 1 Jul 08
• "Colorimetry topic" - 1 Jul 08
• "Flexible & easy to understand with the little background of optical/LED tech" - 1 Jul 08
• "color mixing, color coordinate, radiation patern" - 10 Feb 09
• "Tristimulus, CMF" - 8 Apr 09
• "Understand the derivation of colour coordinate, the relationship of wavelenght and cxcy" - 8 Apr 09

What You Will Learn

• Concepts and measurement of luminous intensity, flux, luminance, illuminance, radiometric power and the inter-relationships between these quantities.
• Concepts and measurement of dominant wavelength, x-y color coordinates, chromaticity diagram and color gamut
• LED emission spectra, photodetector responsivity curves and transmission filters.
• Color matching functions, trisimulus values and color mixing computation.
• Color spaces e.g. CIE , uv and conversion between difference color spaces.
• Color discrimination and color binning.

Who Should AttendThe primary target audience for this course are technicians and engineers involved in product marketing, test and development, characterization, design and development, field installation and maintenance and QA of optoelectronic components and systems especially LED light emission and detection. This course is also applicable to a broad audience from various industries who need to have strong basic understanding of the various concepts, terms and technologies of light and color measurements e.g. in industries such as LCD TV displays, LED Video Displays, paint, textile and advertisement industries.

Examples of target audience :

• Project Managers
• Program Managers
• Test Engineers
• Mechanical Engineers
• Quality and Reliability Engineers
• Failure Analysis Engineers
• Technical Marketing and Sales Engineers

PrerequisiteInterest in the science of light and colors and desire to acquire better conceptual understanding in this area. Technical background in electrical/electronic/mechanical engineering or physics degree would be desirable.

Course MethodologyClass room training.

Course Duration2 days, 9am - 5pm

Course StructurePhotometry

• Photopic function
• Physiological response of the eye
• Luminous Intensity
• Luminous Flux
• Luminance
• Illuminance
• Equivalent radiometric quantities
• Scotopic vs photopic function
• Photopic function and the CIE x-y curve
• Flux measurement and the integrating sphere
• Luminous intensity measurement
• Luminance and illuminance measurements.
• CIE test methodology
• Radiation pattern of emitters or illumination sources.
• Viewing angle measurement

• Anatomy of the eye
• Color specifications
• Dominant wavelength
• Peak wavelength
• X-y color coordinate
• Spectra of LED and other light sources
• Correlated color temperature (CCT)
• Standard Illuminants
• Color rendering index (CRI)
• Descriptive color terms
• Color purity
• Measurement methodologies
• Tristimulus values and color matching functions
• Color mixing - 2 colors mix, 3 colors mix, white and other colors
• Other color spaces - CIE uv, uv, Lab
• Conversion between color spaces
• Natural color gamut
• Color gamut, NTSC (TV) and RGB LEDs
• Color binning and color discrimination - monocolors and white
• Filters, transmissivity and spectra