Thin dual-aperture zoom digital camera

• US 9,413,972 B2
• Filed: 07/04/2014
• Issued: 08/09/2016
• Est. Priority Date: 07/04/2013
• Status: Active Grant

• Current Assignee: Corephotonics Ltd. (Samsung Group)
• Original Assignee: Corephotonics Ltd. (Samsung Group)
• Inventors: Shabtay, Gal, Goldenberg, Ephraim
• Primary Examiner(s): NGUYEN, LUONG TRUNG
• Application Number:
  US14/373,500
• Publication Number:
  US 20150244942A1
• Time in Patent Office: 767 Days
• US Class Current: 1/1
• CPC Class Codes: G02B 1/041 Lenses
• CPC Class Codes: G02B 13/00 Optical objectives specially designed for the purposes specified below with variable magnification in general G02B15/00
• CPC Class Codes: G02B 13/002 having at least one aspherical surface
• CPC Class Codes: G02B 13/004 having four lenses
• CPC Class Codes: G02B 13/0045 having five or more lenses
• CPC Class Codes: G02B 13/009 having zoom function
• CPC Class Codes: G02B 13/02 Telephoto objectives, i.e. systems of the type + - in which the distance from the front vertex to the image plane is less than the equivalent focal length
• CPC Class Codes: G02B 13/18 with lenses having one or more non-spherical faces, e.g. for reducing geometrical aberration G02B13/002 takes precedence
• CPC Class Codes: G02B 27/0025 for optical correction, e.g. distorsion, aberration
• CPC Class Codes: G02B 27/646 compensating for small deviations, e.g. due to vibration or shake movement of one or more optical elements for control of motion blur in cameras, projectors or printers G03B2205/0007; image stabilisation in cameras peculiar to the presence or use of an electronic image sensor H04N23/68
• CPC Class Codes: G02B 5/005 Diaphragms for cameras G03B9/02
• CPC Class Codes: G02B 9/00 Optical objectives characterised both by the number of the components and their arrangements according to their sign, i.e. + or - G02B15/00 takes precedence
• CPC Class Codes: G02B 9/12 having three components only
• CPC Class Codes: G02B 9/60 having five components only
• CPC Class Codes: G02B 9/62 having six components only
• CPC Class Codes: G02B 9/64 having more than six components
• CPC Class Codes: H04N 2101/00 Still video cameras
• CPC Class Codes: H04N 2201/00 Indexing scheme relating to scanning, transmission or reproduction of documents or the like, and to details thereof
• CPC Class Codes: H04N 23/16 Optical arrangements associated therewith, e.g. for beam-splitting or for colour correction
• CPC Class Codes: H04N 23/45 for generating image signals from two or more image sensors being of different type or operating in different modes, e.g. with a CMOS sensor for moving images in combination with a charge-coupled device [CCD] for still images
• CPC Class Codes: H04N 23/57 : Mechanical or electrical details of cameras or camera modules specially adapted for being embedded in other devices
• CPC Class Codes: H04N 23/69 : Control of means for changing angle of the field of view, e.g. optical zoom objectives or electronic zooming
• CPC Class Codes: Y10T 29/4913 : Assembling to base an electrical component, e.g., capacitor, etc.

Abstract

A dual-aperture zoom camera comprising a Wide camera with a respective Wide lens and a Tele camera with a respective Tele lens, the Wide and Tele cameras mounted directly on a single printed circuit board, wherein the Wide and Tele lenses have respective effective focal lengths EFL_W and EFL_T and respective total track lengths TTL_W and TTL_T and wherein TTL_W/EFL_W>1.1 and TTL_T/EFL_T<1.0. Optionally, the dual-aperture zoom camera may further comprise an optical OIS controller configured to provide a compensation lens movement according to a user-defined zoom factor (ZF) and a camera tilt (CT) through LMV=CT*EFL_ZF, where EFL_ZF is a zoom-factor dependent effective focal length.

Claims

1. A dual-aperture zoom camera, comprising:

a) a Wide camera with a respective Wide lens and a Tele camera with a respective Tele lens, the Wide and Tele cameras mounted directly on a single printed circuit board, wherein the Wide and Tele lenses have respective effective focal lengths EFL_W and EFL_T and respective total track lengths TTL_W and TTL_T, wherein TTL_W/EFL_W>

1.1 and TTL_T/EFL_T<

1.0, wherein EFL_T/EFL_W=e, and wherein e is in the range 1.3-2.0; and

b) an optical image stabilization (OIS) mechanism configured to provide a compensation lens movement (LMV) according to a camera tilt (CT) input and a user-defined zoom factor (ZF) through LMV=CT×

EFL_ZF, wherein CT is a camera tilt in radians and EFL_ZF is a zoom-factor dependent effective focal length in millimeters.

2. The dual-aperture zoom camera of claim 1, wherein for ZF=1, EFL_ZF=EFL_W.

3. The dual-aperture zoom camera of claim 1, wherein for ZF=e, EFL_ZF=EFL_T.

4. The dual-aperture zoom camera of claim 1, wherein for a ZF in the range 1<

ZF<

e, EFL_ZF=ZF×

EFL_W.

5. The dual-aperture zoom camera of claim 1, wherein for a ZF in the range ZF>

e, EFL_ZF=EFL_T.

6. The dual-aperture zoom camera of claim 1, wherein a ratio TTL_T/TTL_W is in the range 1.0-1.25.

7. The dual-aperture zoom camera of claim 1, wherein a ratio TTL_T/TTL_W is smaller that 0.8×

(EFL_T/EFL_W).

8. The dual-aperture zoom camera of claim 1, having a dual-aperture zoom camera height of less than 7 mm.

9. A dual-aperture zoom camera, comprising:

a) a Wide camera with a respective Wide lens and a Tele camera with a respective Tele lens, the Wide and Tele cameras mounted directly on a single printed circuit board, wherein the Wide and Tele lenses have respective effective focal lengths EFL_W and EFL_T and respective total track lengths TTL_W and TTL_T and wherein TTL_W/EFL_W>

1.1 and TTL_T/EFL_T<

1.0,

wherein the Tele lens comprises a first lens element with positive refractive power having a convex object-side surface, a second lens element with negative refractive power having a thickness d₂ on an optical axis and separated from the first lens element by a first air gap, a third lens element with negative refractive power and separated from the second lens element by a second air gap, a fourth lens element having a positive refractive power and separated from the third lens element by a third air gap, and a fifth lens element having a negative refractive power, separated from the fourth lens element by a fourth air gap, the fifth lens element having a thickness d₅ on the optical axis; and

b) a single magnetic shield plate positioned between the Wide and Tele cameras, wherein the single magnetic shield plate has a plate length and a plate height no larger than a respective length and height of either of the Wide or Tele cameras,

wherein a focal length of the first lens element f1 is smaller than TTL_T/2, the first, third and fifth lens elements have each an Abbe number greater than 50, the second and fourth lens elements have each an Abbe number smaller than 30, the first air gap is smaller than d₂/2, the third air gap is greater than TTL_T/5 and the fourth air gap is smaller than 1.5d₅.

10. A method for manufacturing a dual-aperture zoom camera comprising the steps of:

a) providing a Wide camera having a Wide lens with an effective focal length (EFL) EFL_W and a total track length (TTL) TTL_W;

b) providing a Tele camera having a Tele lens with an effective focal length EFL_T and a total track length TTL_T, wherein TTL_W/EFL_W>

1.1 and TTL_T/EFL_T<

1.0, wherein EFL_T/EFL_W=e and wherein e is in the range 1.3-2.0;

c) mounting the Wide and Tele cameras directly on a single printed circuit board; and

d) configuring an optical image stabilization (OIS) controller of the dual-aperture zoom camera to compensate lens movement (LMV) of the Wide and Tele lenses according to a camera tilt (CT) input in radians and a user-defined zoom factor (ZF), wherein LMV=CT×

EFL_ZF and wherein EFL_ZF is a zoom-factor dependent effective focal length in millimeters.

11. The method of claim 10, wherein for ZF=1, EFL_ZF=EFL_W.

12. The method of claim 10, wherein for ZF=e, EFL_ZF=EFL_T.

13. The method of claim 10, wherein for a ZF in the range 1<

ZF<

e, EFL_ZF=ZF×

EFL_W.

14. The method of claim 10, wherein for a ZF in the range ZF>

e, EFL_ZF=EFL_T.

15. The method of claim 10, wherein a ratio TTL_T/TTL_W is in the range 1.0-1.25.

16. The method of claim 10, wherein a ratio TTL_T/TTL_W is smaller than 0.8×

(EFL_T/EFL_W).

17. The method of claim 10, wherein the step of providing the Tele camera having the Tele lens with the effective focal length EFL_T and the total track length TTL_T includes providing a Tele lens comprising a first lens element with positive refractive power having a convex object-side surface, a second lens element with negative refractive power having a thickness d₂ on an optical axis and separated from the first lens element by a first air gap, a third lens element with negative refractive power and separated from the second lens element by a second air gap, a fourth lens element having a positive refractive power and separated from the third lens element by a third air gap, and a fifth lens element having a negative refractive power, separated from the fourth lens element by a fourth air gap, the fifth lens element having a thickness d₅ on the optical axis.

18. The method of claim 17, wherein the focal length of the first lens element f1 is smaller than TTL_T/2, the first, third and fifth lens elements have each an Abbe number greater than 50, the second and fourth lens elements have each an Abbe number smaller than 30, the first air gap is smaller than d₂/2, the third air gap is greater than TTL_T/5 and the fourth air gap is smaller than 1.5d₅.