1. A transfer efficiency enhancement method for enhancing a transfer efficiency by controlling a transfer voltage output from a transfer voltage generator through a pulse-width modulation command under the control of a microcomputer according to a transfer environment and a paper sheet recognition in electronic photograph development equipment, the transfer efficiency enhancement method comprising: recognizing a transfer environment by increasing a transfer voltage up to a predetermined value until a trigger is triggered before a sheet of paper is fed, according to an analog-to-digital conversion value of a fedback transfer voltage; recognizing the sheet of paper by applying the transfer voltage determined through recognition of the transfer environment to a leading end of the sheet of paper, in order to perform recognition and transfer of the sheet of paper; and controlling the transfer voltage based on an output value from an analog-to-digital converter (ADC) which is obtained in a result of the paper sheet recognition, in which the transfer voltage is controlled to become a first state if the ADC output value is large, but the transfer voltage is controlled to become a second state different from the first state if the ADC output value is small.