Optical system for an automated luminaire

Patent metadata

Field	Value
Publication number	US-12345390-B2
Application number	US-202418799778-A
Country	US
Kind code	B2
Filing date	Aug 9, 2024
Priority date	Aug 30, 2023
Publication date	Jul 1, 2025
Grant date	Jul 1, 2025

Abstract

A zoom optical system includes a light source and focus, zoom, and fixed lens groups. The light source illuminates an object in or adjacent to an object plane. The focus lens group has a first positive optical power and moves to focus an object. The focus lens group has four lenses of positive, positive, positive, and negative optical power. The zoom lens group has a negative optical power and moves relative to the object plane and the focus lens group to control a beam angle while the focus lens group remains fixed relative to the object plane. The zoom lens group comprises two negative power lenses. The fixed lens group has a second positive optical power, remains in a fixed position relative to the object plane, and projects an image of the object. The fixed lens group has three lenses, comprising negative, positive, and positive optical powers.

First claim

What is claimed is:

1. A zoom optical system comprising:
a light source configured to illuminate an object located in an object plane of the zoom optical system or in a plane adjacent to the object plane;
a focus lens group optically coupled to the object without intervening lenses, the focus lens group having a first positive optical power and configured to move relative to the object plane to control whether the object is in focus, the focus lens group comprising four lenses, the four lenses comprising positive, positive, positive, and negative optical power lenses, listed in sequence beginning with a lens of the focus lens group closest to the object plane;
a zoom lens group optically coupled to the focus lens group without intervening lenses, the zoom lens group having a negative optical power and configured to move relative to the object plane and the focus lens group, the zoom lens group configured to move to control a beam angle while the focus lens group remains in a fixed position relative to the object plane, the zoom lens group comprising two lenses, both lenses comprising negative power lenses; and
a fixed lens group, optically coupled to the zoom lens group without intervening lenses, the fixed lens group having a second positive optical power, and configured to remain in a fixed position relative to the object plane and to project an image of the object, the fixed lens group comprising three lenses, the three lenses comprising negative, positive, and positive optical power lenses, listed in sequence beginning with a lens of the fixed lens group closest to the object plane.

2. The zoom optical system of claim 1 , wherein the focus lens group and the zoom lens group are further configured to be moved to selected positions relative to each other by an operator of the zoom optical system.

3. The zoom optical system of claim 1 , wherein the focus lens group and the zoom lens group are configured to be moved to selected positions relative to each other by a remotely located operator of the zoom optical system.

4. The zoom optical system of claim 1 , wherein:
the four lenses of the focus lens group comprise crown glass, flint glass, crown glass, and flint glass, listed in sequence beginning with the lens of the focus lens group closest to the object plane;
the two lenses of the zoom lens group both comprise crown glass; and
the three lenses of the fixed lens group comprise flint glass, crown glass, and crown glass, listed in sequence beginning with the lens of the fixed lens group closest to the object plane.

5. The zoom optical system of claim 4 , wherein:
the four lenses of the focus lens group comprise glass of types H-K9L, H-ZFL7A, H-K9L, and H-ZFL7A, listed in sequence beginning with the lens of the focus lens group closest to the object plane;
the two lenses of the zoom lens group comprise glass of types H-ZK9A; and
the three lenses of the fixed lens group comprise glass of types H-ZFL7A, H-K9L, and H-K9L, listed in sequence beginning with the lens of the fixed lens group closest to the object plane.

6. The zoom optical system of claim 1 , wherein:
the lenses of the focus lens group, listed in sequence beginning with the lens of the focus lens group farthest from the object plane, have substantially the following radii of curvature:

R1
R2

−113.4
79.4

242.5
−41.7

−487.8
−161.6

44.5
−144.1;

the lenses of the zoom lens group, listed in sequence beginning with the lens of the zoom lens group farthest from the object plane, have substantially the following radii of curvature:

R1
R2

−331.7
146.5

−265.2
73.8;

and
the lenses of the fixed lens group, listed in sequence beginning with the lens of the fixed lens group farthest from the object plane, have substantially the following radii of curvature:

R1
R2

316.6
−960.3

178.0
−511.2

−511.2
591.2,

where R1 is a radius of curvature of an image side surface of the lens, a positive value of R1 indicating a convex image side surface, and a negative value of R1 indicating a concave image side surface; R2 is a radius of curvature of an object side of the lens, a positive value of R2 indicating a concave object side surface, and a negative value of R2 indicating a convex object side surface; and all radii are expressed in millimeters.

7. An automated luminaire, comprising:
a light source configured to emit a first light beam and illuminate an object located in an object plane of the automated luminaire or in a plane adjacent to the object plane;
a zoom optical system optically coupled to the light source, the zoom optical system comprising:
a focus lens group having a first positive optical power, the focus lens group configured to receive the first light beam as modified by the object, to emit a second light beam, and to move relative to the object to control whether

Assignees

• Robe Lighting Sro

Inventors

• Stanek Michal
• Vilem Jan
• David Tomas
• Vavrik Jindrich
• Valchar Josef

Classifications

• F21W2131/406

  for theatres, stages or film studios · CPC title

• F21V14/06 Primary

  by movement of refractors {(in vehicle head lamps F21S41/635)} · CPC title

• F21V5/008

  Combination of two or more successive refractors along an optical axis · CPC title

• G02B15/143105

  arranged +-+ · CPC title

• F21Y2113/00

  Combination of light sources · CPC title