three.js/src/cameras/OrthographicCamera.js

/**
 * @author alteredq / http://alteredqualia.com/
 */

THREE.OrthographicCamera = function ( left, right, top, bottom, near, far ) {

	THREE.Camera.call( this );

	this.left = left;
	this.right = right;
	this.top = top;
	this.bottom = bottom;

	this.near = ( near !== undefined ) ? near : 0.1;
	this.far = ( far !== undefined ) ? far : 2000;

	this.updateProjectionMatrix();

};

THREE.OrthographicCamera.prototype = new THREE.Camera();
THREE.OrthographicCamera.prototype.constructor = THREE.OrthographicCamera;

THREE.OrthographicCamera.prototype.updateProjectionMatrix = function () {

	this.projectionMatrix = THREE.Matrix4.makeOrtho( this.left, this.right, this.top, this.bottom, this.near, this.far );

};