# Power Area Density in Inverse Spectra

## TL;DR

This paper investigates the power area density of inverse spectra across ultraviolet, visible, and infrared ranges, providing experimental evidence for spectral regions like ultra-yellow and infra-cyan, supporting the additivity and inversion properties of inverse spectra.

## Contribution

It presents the first measurement of power area density in inverse spectra across multiple spectral ranges, confirming their additive and inversion characteristics beyond visible light.

## Key findings

- Existence of ultra-yellow and infra-cyan regions in inverse spectra
- Inverse spectra add up to a constant intensity level
- Experimental validation of spectral inversion properties

## Abstract

In recent years, inverse spectra were investigated with imaging optics and a quantitative description with radiometric units was suggested (Rang 2015). It could be shown that inverse spectra complement each other additively to a constant intensity level. Since optical intensity in radiometric units is a power area density, it can be expected that energy densities of inverse spectra also fulfill an inversion equation and complement each other. In this contribution we report findings on a measurement of the power area density of inverse spectra for the near ultraviolet, visible and the infrared spectral range. They show the existence of corresponding spectral regions ultra-yellow (UY) and infra-cyan (IC) in the inverted spectrum and thereby present additional experimental evidence for equivalence of inverse spectra beyond the visible range.

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Source: https://tomesphere.com/paper/1706.09063