Final answer:
For blood smear evaluation, the 100X oil immersion objective is recommended because it provides high magnification and resolution, essential for detailed analysis of cell structures. This objective achieves 1000X magnification with a resolution of 0.2 µm, and the use of immersion oil is necessary to enhance image clarity.
Step-by-step explanation:
When evaluating a blood smear under a microscope, the objective that is recommended is the 100X oil immersion objective. The oil immersion lens is specifically designed to achieve high magnification with superior resolution, essential for detailed analysis of cell structures, such as red and white blood cells in a blood smear. It increases the resolving power, which is the microscope's ability to distinguish two adjacent structures as separate entities, enhancing the clarity and detail of the image.
The 100X oil immersion lens reaches a magnification of 1000 times, providing a resolution of 0.2 micrometers. Staining the blood smear with selective dyes also helps in increasing the contrast, allowing for the clearer visualization of cellular components. The use of immersion oil is crucial with the 100X objective as it prevents refraction of light rays, which could otherwise reduce image quality. Always remember to clean the oil from the lens after use, as oil can damage the lenses over time if not removed.
Overall, the 100X oil immersion objective is the preferred lens for blood smear evaluation, as it provides the necessary magnification and resolution to conduct a detailed analysis of cells.