A method for designing a printed circuit board to meet a specification is described. Tabs 30 are attached to the blade holder 22 to assist in aligning the blade assembly 18 with a mating slot 12 in a microkeratome to minimize damage to the cutting blade 20. The circuit includes a means for producing a voltage offset from the common mode voltage of the class AB transconductors. In some implementations, the additional documents may be presented in-line with the document being read, such as through an in-link link or text snippet.