---
title: "init(verticalAmount:verticalBase:horizontalAmount:horizontalBase:eye:)"
framework: healthkit
role: symbol
role_heading: Initializer
path: "healthkit/hkvisionprism/init(verticalamount:verticalbase:horizontalamount:horizontalbase:eye:)"
---

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

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

## Declaration

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

## Parameters

- `verticalAmount`: The vertical strength of the correction, measured in doc://com.apple.healthkit/documentation/HealthKit/HKUnit/prismDiopter() units.
- `verticalBase`: The orientation of the vertical correction. This value can be either doc://com.apple.healthkit/documentation/HealthKit/HKPrismBase/up or doc://com.apple.healthkit/documentation/HealthKit/HKPrismBase/down.
- `horizontalAmount`: The horizontal strength of the correction, measured in doc://com.apple.healthkit/documentation/HealthKit/HKUnit/prismDiopter() units.
- `horizontalBase`: The orientation of the horizontal correction. This value can be either doc://com.apple.healthkit/documentation/HealthKit/HKPrismBase/in or doc://com.apple.healthkit/documentation/HealthKit/HKPrismBase/out.
- `eye`: A value indicating which eye the correction applies to: doc://com.apple.healthkit/documentation/HealthKit/HKVisionEye/left or doc://com.apple.healthkit/documentation/HealthKit/HKVisionEye/right.

## See Also

### Creating vision prism objects

- [init(amount:angle:eye:)](healthkit/hkvisionprism/init(amount:angle:eye:).md)