<abstract xmlns="http://www.w3.org/1999/xhtml"><p> One of the advantages of a source method over observer method in blur perception measurements is better control of a stimulus blur level, which is achieved with computerised image processing unlike the observer method that requires optical defocusing of the observer. The aim of this study was to determine if paralysation of accommodation has effect on blur perception thresholds, thereby evaluating its necessity in such experiments. Blur perception thresholds (just noticeable blur, clear image, recognition, and non-resolvable blur thresholds) were evaluated with (using cycloplegia) and without paralysed accommodation to determine effect on blur perception. A computerised low-pass spatial frequency filter was used to process images of Landolt rings and gradually increase the blur level from the stage of clear image to the stage of unrecognisable orientation of Landolt ring opening. Ascending and descending psychophysical methods were used to evaluate the previously mentioned blur perception thresholds. Results for 10 participants revealed no significant effect of cycloplegia on any of the determined blur perception thresholds. Therefore, it may be considered that blur perception measurements with source method can be done without cycloplegia.</p></abstract>

One of the advantages of a source method over observer method in blur perception measurements is better control of a stimulus blur level, which is achieved with computerised image processing unlike the observer method that requires optical defocusing of the observer. The aim of this study was to determine if paralysation of accommodation has effect on blur perception thresholds, thereby evaluating its necessity in such experiments. Blur perception thresholds (just noticeable blur, clear image, recognition, and non-resolvable blur thresholds) were evaluated with (using cycloplegia) and without paralysed accommodation to determine effect on blur perception. A computerised low-pass spatial frequency filter was used to process images of Landolt rings and gradually increase the blur level from the stage of clear image to the stage of unrecognisable orientation of Landolt ring opening. Ascending and descending psychophysical methods were used to evaluate the previously mentioned blur perception thresholds. Results for 10 participants revealed no significant effect of cycloplegia on any of the determined blur perception thresholds. Therefore, it may be considered that blur perception measurements with source method can be done without cycloplegia.

Effect of Cycloplegia on Blur Perception Thresholds as Measured by Source Method

Proceedings of the Latvian Academy of Sciences. Section B. Natural, Exact, and Applied Sciences.

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

{"article-title":"Effect of Cycloplegia on Blur Perception Thresholds as Measured by Source Method"}

One of the advantages of a source method over observer method in blur perception measurements is better control of a stimulus blur level, which is achieved...

Effect of Cycloplegia on Blur Perception Thresholds as Measured by Source Method

Published Online: Nov 14, 2017

Page range: 347 - 351

Received: Oct 02, 2016

Accepted: Jul 28, 2017

DOI: https://doi.org/10.1515/prolas-2017-0059

Keywords
blur perception, blur adaptation, source blurring method, cycloplegia, Gaussian blur filter

© by Anete Petrova

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Effect of Cycloplegia on Blur Perception Thresholds as Measured by Source Method

Published Online: Nov 14, 2017

Page range: 347 - 351

Received: Oct 02, 2016

Accepted: Jul 28, 2017

DOI: https://doi.org/10.1515/prolas-2017-0059

Keywordsblur perception, blur adaptation, source blurring method, cycloplegia, Gaussian blur filter

© by Anete Petrova

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Keywords
blur perception, blur adaptation, source blurring method, cycloplegia, Gaussian blur filter