refractive index of immersion oil verses water

[april]

Viewing a slide under a microscope, What would happen if water were used in place of immersion oil?
I know that immersion oil has a refractive index (N=1.52) which is the same as glass. I believe water has the same refractive index as air, so viewing under water on a microscope would be like having nothing on a slide, am I correct?

The refraction index for water is about 4/3. It is not the same as air (refraction index is very close to 1)

[Draco02]

There is a common misconception that when half of a lens is covered that half of the image disappears. This problem can be helped by two methods. First, the simulation should be capable of drawing extra rays to show that there are multiple rays going through the lens. This would be a useful option for the thin lens applet.

[Fu-Kwun Hwang]

You are welcomed to check out What happened to the image if part of the light path were blocked