Sturms’s Conoid and Circle of Least confusion

[tbearOD]

So none of my professor have effectively explained the significance/relevance
I understand that sturms’s conoid is the difference between the two focal points created by the vertical and horizontal meridians and that the circle of confusion is the diopter midway between

but is this speaking in terms of the lens of a spectacle of the the crystalline lens

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[Snakedoctor1]

the optical properties of an astigmatic lens apply to both the crystalline lens as well as corrective toric lenses. When a person has astigmatism, they will have essentially two focal points created by light passing through all of the refractive surfaces of the eye. Now you have two focal points that need to be collapsed as close together as they can so that you can achieve as close to a single focal point on the retina as possible.

In other words, because of the toric refractive surfaces of the eye creating Sturm's interval near the retina, you now need a similarly (but opposite) toric corrective lens in order to collapse Sturm's interval into the circle of lease confusion. Now those two focal points are fairly close together and focused on the retina, and your astigmatic patient gives you a big hug. Aww..