This file is from Wikimedia Commons and may be used by other projects.
The description on its file description page there is shown below.
Summary
DescriptionBirdVisualPigmentAbsorbance.svg
English: Uncorrected absorbances of visual pigments of birds (alternative to File:Tetrachromaticpigments01.png) based on Pryke, Sarah R. (2007) Sexual selection of Ultraviolet and structural color signals in Reproductive biology and phylogeny of birds/volume 6a-6b edited by Barrie G.M. Jamieson. pages 1-40. This book cites Hart NS, Partridge JC, Bennett ATD and Cuthill IC (2000) Visual pigments, cone oil droplets and ocular media in four species of estrildid finch. Journal of Comparative Physiology A186 (7-8): 681-694 for the data, curve fits, and method; online here.
Русский: Четыре типа пигментации колбочек птиц (в данном примере это вьюрковые ткачики) расширяют цветовой диапазон их видения до области ультрафиолета.
I, the copyright holder of this work, release this work into the public domain. This applies worldwide. In some countries this may not be legally possible; if so: I grant anyone the right to use this work for any purpose, without any conditions, unless such conditions are required by law.
Captions
The four pigments in a bird's cone cells (in this example, estrildid finches) extend the range of color vision into the ultraviolet.