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# init(amount:angle:eye:)

Creates a new vision prism object, using a single quantity and an alignment angle.

```
init(amount: HKQuantity, angle: HKQuantity, eye: HKVisionEye)
```

## Parameters

`amount`

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

`angle`

The orientation of the adjustment, measured in [`degreeAngle()`](/documentation/HealthKit/HKUnit/degreeAngle()) units.

`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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