Nowadays, there are many method for medical identification that exist for example based on microscopic and nonmicroscopic. Microscopic is a method that use microscope to capture an image and identify the disease based on the image captured. The image quality of medical image is very important for patient diagnosis. Image with poor contrast and the quality of the image is not good may lead to the mistaken decision, even in experienced hands. Therefore, contrast enhancement methods was proposed in order to enhance the image quality. Contrast enhancement is a process that improves the contrast of an image to make various features more easily perceived. Contrast enhancement is widely used and plays important roles in image processing application. This paper review the contrast enhancement techniques was used in microscopic images. There are microscopic images for cervical cancer, leukemia, malaria, tuberculosis and anemia.
