Our bee eye model is based on measurements reported in [1,2] and extends the model described in [3] to the full field of view of the eyes of a worker bee. The model generates 5453 ommatidia (pixels) per eye (see http://biology.anu.edu.au/jochen_zeil/crab_eye_tutorial/ for a tutorial on compound eyes). The viewing directions of all ommatidia of both compound eyes, i.e. their azimuth and elevation angles, are shown in Figure 1. As can bee seen, the resolution is highest (the inter-ommatidial angle is smallest) along the horizon (elevation angle 0°) and near ±45° azimuth. The model varies the horizontal inter-ommatidial angle between 2.4° and 4.6° and the vertical inter-ommatidial angle between 1.5° and 4.5°. The viewing angle (or field of view) of each ommatidium is adapted to the local resolution, such that it is larger for regions with lower density of ommatidia and vice versa. For further details see [4]. So far, our bee eye model does not take the colour vision of bees into account. The RGB-colours resemble the spectral sensitivity of humans. In comparison, the eyes of bees are much less sensitive to red light, but can see light in the near UV range. Furthermore, the region of the eye that is usually oriented towards the sky is also sensitive to the polarisation of light.
Figure 1. Viewing directions of ommatidia as generated by the bee eye model
References
[1] R. Seidl, W. Kaiser. Visual field size, binocular domain and the ommatidial array of the compound eyes in worker honey bees. J. Comp. Physiol. A 143:17–26 (1981).
[2] R. Seidl. Die Sehfelder und Ommatidien-Divergenzwinkelvon Arbeiterin, Königin und Drohn der Honigbiene (Apis mellifica). PhD Thesis Technische Hochschule Darmstadt (1982).
[3] A.D. Giger. Honeybee vision: analysis of pattern orientation. PhD Thesis Australian National University (1996).
[4] W. Stürzl, N. Boeddeker, L. Dittmar, M. Egelhaaf. Mimicking honeybee eyes with a 280° FOV catadioptric imaging system. Bioinspiration & Biomimetics 5 (2010).
