Infrared Theory

Advance your spectrum warfare knowledge by examining aspects of infrared theory, including key terms, definitions and basic laws, and its applications in the military.

Enroll in ICFA121

About This Intelligence Community Online Course

Increase your understanding of infrared theory and its relevance to spectrum warfare by taking this self-paced, online course created by FedLearn content partner, PatchPlus Consulting.

You will learn what IR radiation is and where it exists on the electromagnetic spectrum. In addition, the course covers lasers as a special form of IR energy; a variety of important, IR-related terms and definitions; basic scientific laws that expand our understanding of how IR energy behaves; detection considerations; basic ir sensors; and several commercial and military applications. This knowledge will advance your understanding of how IR applications contribute to the development of low observable technology and spectrum warfare.

This online training course is comprised of several short lessons made of video lectures, discussion prompts to promote virtual, peer-to-peer learning and information sharing and graded knowledge checks. You will be required to take, and pass, a final exam.

Throughout the course, real-world examples of IR theory applications will be explored.

This course is part of the FedLearn spectrum warfare learning series.

What You Will Learn

  • Understand EM fundamentals
  • Understand lasers
  • Describe albedo, emissivity, blackbody, radiometry, photometry, radiant flux, radiant intensity, radiance, irradiance and radiant exitance
  • Understand Planck’s law, Kirchhoff’s law, Wien’s displacement law, Lambert’s cosine law and Stefan-Boltzmann’s law
  • Identify the differences between reflected and thermal infrared energy
  • Describe surface versus effective emissivity
  • Describe the inverse square law and how it relates to the transmission and detection of IR energy
  • Understand IR detection considerations, detection problems and spatial resolution
  • IR sensor basics, key elements of an IR detection system, how an IR sensor works and IR sensor applications and their advantages and disadvantages
  • Describe IR detection system components
  • Understand specific IR detections, infrared countermeasures, imaging systems, video trackers, terminal homing seekers and automatic target recognition

Your Instructor

The course was developed by Robert Folker and a combination of several subject matter experts from PatchPlus Consulting.

Mr. Folker is a retired U.S. Air Force intelligence weapons instructor with more than 30 years of military experience in technological development for various military applications. He currently is a senior strategist and intelligence, surveillance and reconnaissance consultant with PatchPlus Consulting.

Mr. Folker a senior subject matter expert on indications and warning, sensitive reconnaissance operations, ISR planning, sensor employment and numerous intelligence disciplines that span the range from unit-level to national-level organizations, cyber operations, U.S. and adversary weapon systems and transregional threats.

He is both a graduate of and former instructor at the USAF Weapons School and earned his Master of Science in Strategic Intelligence from the National Intelligence University.

Who Should Take This Online Course

This online course is perfect for anyone who wishes to learn about (or gain a refresher on) IR theory and spectrum warfare—particularly, defense or intelligence analysts working in either Federal government agencies or government contractor companies.


None. However, it is highly recommended that you take the FedLearn course, EM Fundamentals (ICFA118), prior to taking this course.

After completing this course, it is highly recommended you take the other FedLearn courses in the spectrum warfare learning series, Basic Communications (ICFA120) and Low Observable Theory (ICFA122), to continue to advance your knowledge.

Course Certificate

To achieve a course certificate of completion, you must score 80 percent or higher on graded lesson quizzes and a final exam.

Course Format

Self-paced, online training course

Course Pricing

Individual courses are $124.99 (per person).

Seat licenses to access the entire FedLearn Intelligence Community catalog are also available. Click here to learn more and purchase.

If you are interested in learning about special team rates for Federal government and government contractor organizations, email [email protected].

Continuing Education Unit Credits

This course provides 2 CEUs.