**The Geometry and Usage of the Supplementary Fisheye Lenses in Smartphones** Provisional chapter The Geometry and Usage of the Supplementary Fisheye

DOI: 10.5772/intechopen.69691

Cumhur Sahin

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24 Smartphones from an Applied Research Perspective

Additional information is available at the end of the chapter Cumhur Sahin

http://dx.doi.org/10.5772/intechopen.69691 Additional information is available at the end of the chapter

Lenses in Smartphones

#### Abstract

Nowadays, mobile phones are more than a device that can only satisfy the communication need between people. Since fisheye lenses integrated with mobile phones are lightweight and easy to use, they are advantageous. In addition to this advantage, it is experimented whether fisheye lens and mobile phone combination can be used in a photogrammetric way, and if so, what will be the result. Fisheye lens equipment used with mobile phones was tested in this study. For this, standard calibration of 'Olloclip 3 in one' fisheye lens used with iPhone 4S mobile phone and 'Nikon FC-E9' fisheye lens used with Nikon Coolpix8700 are compared based on equidistant model. This experimental study shows that Olloclip 3 in one fisheye lens developed for mobile phones has at least the similar characteristics with classic fisheye lenses. The dimensions of fisheye lenses used with smart phones are getting smaller and the prices are reducing. Moreover, as verified in this study, the accuracy of fisheye lenses used in smartphones is better than conventional fisheye lenses. The use of smartphones with fisheye lenses will give the possibility of practical applications to ordinary users in the near future.

Keywords: smartphone, fisheye lenses, equidistant projection model, distortion geometry, supplementary lenses
