Introduction

  The human eyes cannot perceive objects that are smaller than a certain size. Also, they cannot recognize light whose intensity is lower than an inherent threshold. We take these limitations into account to determine the number of fluorescent proteins that must accumulate before we can notice any fluorescence, and establish the minimum circular area required for us to perceive any fluorescence.

  Objective

  Investigate concentration required for an amount of fluorescent protein in the E.coli that makes light from E.coli be visible for human.

  Background

  Human has the limits in vision. For our objective, we have to know about the limit of recognizing size of objects in human vision. This limit is called the ‘Minimum visible acuity’. The exact definition of minimum visible acuity is the minimum size of object that the human eyes can discern. In the table 1 Types of visual acuity(reference 1), the value of detection acuity(red box), ~1.0 arc second, is the minimum visible acuity that we take.