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# init(verticalAmount:verticalBase:horizontalAmount:horizontalBase:eye:)

Creates a new vision prism object that separates the correction strength into horizontal and vertical components.

```
init(verticalAmount: HKQuantity, verticalBase: HKPrismBase, horizontalAmount: HKQuantity, horizontalBase: HKPrismBase, eye: HKVisionEye)
```

## Parameters

`verticalAmount`

The vertical strength of the correction, measured in [`prismDiopter()`](/documentation/HealthKit/HKUnit/prismDiopter()) units.

`verticalBase`

The orientation of the vertical correction. This value can be either [`HKPrismBase.up`](/documentation/HealthKit/HKPrismBase/up) or [`HKPrismBase.down`](/documentation/HealthKit/HKPrismBase/down).

`horizontalAmount`

The horizontal strength of the correction, measured in [`prismDiopter()`](/documentation/HealthKit/HKUnit/prismDiopter()) units.

`horizontalBase`

The orientation of the horizontal correction. This value can be either [`HKPrismBase.in`](/documentation/HealthKit/HKPrismBase/in) or [`HKPrismBase.out`](/documentation/HealthKit/HKPrismBase/out).

`eye`

A value indicating which eye the correction applies to: [`HKVisionEye.left`](/documentation/HealthKit/HKVisionEye/left) or [`HKVisionEye.right`](/documentation/HealthKit/HKVisionEye/right).

---

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