In a OCT interferometer it is necessary to balance dispersion within the reference aim with dispersion within the object aim. This is normaly done by replicating within the reference aim the components found in the object aim. This adds to the complexity and cost of the OCT interferometer. A method is provided for determining the design of and designing a simplified OCT interferometer, in which the reference aim contains only a single piece of glass of a single glass type. This reduces the cost and complexity of the OCT interferometer, and reduces power loss and undesired reflections within the reference arm.