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  "title" : "HKPrismBase"
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# HKPrismBase

The orientation of the prism correction, represented by the location of the prism’s base (the thickest part of the prism).

```
enum HKPrismBase
```

## Topics

### Prism Base

[`case none`](/documentation/HealthKit/HKPrismBase/none)

No prism correction.

[`case up`](/documentation/HealthKit/HKPrismBase/up)

The prism’s base is at the top of the lens.

[`case down`](/documentation/HealthKit/HKPrismBase/down)

The prism’s base is at the bottom of the lens.

[`case `in``](/documentation/HealthKit/HKPrismBase/in)

The prism base is on the inside edge of the lens.

[`case out`](/documentation/HealthKit/HKPrismBase/out)

The prism base is on the outside edge of the lens.

### Initializers

[`init?(rawValue: Int)`](/documentation/HealthKit/HKPrismBase/init(rawValue:))

## Relationships

### Conforms To

[`Hashable`](/documentation/Swift/Hashable)

[`Equatable`](/documentation/Swift/Equatable)

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

[`RawRepresentable`](/documentation/Swift/RawRepresentable)

[`BitwiseCopyable`](/documentation/Swift/BitwiseCopyable)

[`Sendable`](/documentation/Swift/Sendable)

---

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