---
title: "Electro-Optic Deflection calculator — AperiOptic"
description: "Deflection angle from EO crystal under applied voltage. Free online optics calculator, with the formula and code snippets."
url: "https://aperioptic.com/calculators/electro-optic-deflection"
---

# Electro-Optic Deflection calculator

Deflection angle from EO crystal under applied voltage.

Category: [Scanning](https://aperioptic.com/calculators)

Formula: `θ = n³·r·(L/d)·(V/d) / 2`

## Inputs

| Input | Parameter | Unit | Default |
| --- | --- | --- | --- |
| Index n | `n` |  | 2.2 |
| EO coef. r | `r` | pm/V | 30 |
| Length L | `L` | mm | 20 |
| Aperture d | `d` | mm | 2 |
| Voltage | `V` | V | 1000 |

## Result with the default inputs

- Deflection: 0.7986 mrad
- Deflection: 0.0458 °

Open it with your own values: put each input in the address as a parameter, for example [`/calculators/electro-optic-deflection?n=2.2`](https://aperioptic.com/calculators/electro-optic-deflection?n=2.2). A unit other than the listed one goes in `<parameter>_unit`.

Read more: [Wikipedia: Electro-optic modulator](https://en.wikipedia.org/wiki/Electro-optic_modulator)

[All optics calculators](https://aperioptic.com/calculators)

---

The interactive page: https://aperioptic.com/calculators/electro-optic-deflection (AperiOptic runs in the browser; free, no account). Every page of the site as Markdown: https://aperioptic.com/llms.txt