Achieving a wide instantaneous bandwidth and wide scanning capabilities are essential for development of (sub)millimeter imaging spectrometers for astronomical observations. Such an instrument can be realized using complex quasi-optical (QO) systems. In this work, we propose a QO architecture based on refractive components to reduce the overall size and volume of the instrument. This compact design is optimized using a sequential Geometrical Optics based technique. The performance of the preliminary design is reported in terms of the aperture efficiency over an octave of bandwidth and the field of view of the telescope hosting the instrument exhibiting less than 1dB of scan loss. The finalized design of the instrument, its performance, and realization approach will be discussed at the conference.