Consumer's product selection measures are being shifted from the units' operational performance to overall performance. High quality image that required “no banding, good color alignment, etc.” which used to be important evaluation indices, now became vital performance factors. To satisfy customer's needs about image quality, development of evaluation tools for measurement of image arrangement or banding is urgently needed and each company's own up-to-date special tools and standards are used in manufacturing goods. One of the major image quality issues is known as banding which is related to the fluctuations of the internal printer components. Accumulated errors from instability of controlling belts or tolerance of gears operating in photographic and fusing systems make thick band characteristic which is low frequency banding. This paper describes the phenomenon of high frequency banding from Laser Scanning Unit (LSU) which causes thin banding characteristic. As printers' trend move towards smaller size, color tandem type of LSU is becoming more compact than it was. Image banding occurred due to optomechanic positions, characteristics of optic parts (lens, mirrors, etc.) and beam path in LSU. Image banding evaluation analysis with some cases are compared and discussed on experimental and analytic results.