Assertion: microscope's objective | /r/HasProperty | marked with their magnification
Facets:
value: in lieu of focal length
type: CAUSE
Source sentences:
text: Objectives are marked with their magnification (in lieu of focal length) and numerical aperture, which is the product of the refractive index of the medium in front of the lens, such as air, water or immersion oil, and the sine of the angle between the optical axis and the most divergent ray that will make it to the image.