Miniature telephoto lens module and a camera utilizing such a lens module
The presently disclosed subject matter includes a mobile electronic comprising an integrated camera, comprising a Wide camera unit comprising a Wide lens unit, and a Telephoto camera unit comprising a telephoto lens unit, the telephoto lens unit and the wide lens unit having respectively TTL/EFL ratios smaller and larger than 1 and defining separate telephoto and wide optical paths.
1. A mobile electronic device comprising an integrated camera, wherein the camera comprises a Wide camera unit comprising a Wide lens unit with a field of view FOV W and having a total track length TTL W and an effective focal length EFL W in the range 2.5-6 mm, and a Telephoto camera unit comprising a Telephoto lens unit with a Telephoto field of view FOV T , a total track length TTL T and an effective focal length EFL T in the range 5-12 mm, wherein the Telephoto lens unit has a F # smaller than 3.2 and an optical diameter smaller than 5 mm, wherein the TTL T includes a glass window, wherein a ratio TTL W /EFL W is greater than 1, and wherein a ratio TTL T /EFL T is smaller than 1.
2. The mobile electronic device of claim 1 , wherein the Wide and Telephoto camera units define separate Wide and Telephoto optical paths and are spaced apart from each other a distance d of about 1 mm.
3. The mobile electronic device of claim 1 , wherein light receiving outer surfaces of the Wide and Telephoto lens units are located substantially in the same plane, thereby reducing shadowing and light blocking effects therebetween.
4. The mobile electronic device of claim 1 , wherein the Wide and Telephoto camera units are mounted on separate printed circuit boards.
5. The mobile electronic device of claim 4 , wherein the printed circuit boards are located in different spaced-apart substantially parallel planes.
6. The mobile electronic device of claim 1 , wherein the Wide and Telephoto camera units are mounted directly on a single printed circuit board.
7. The mobile electronic device of claim 1 , wherein the Telephoto lens unit is made of at least two polymer materials.
8. The mobile electronic device of claim 1 , wherein TTL T is less than 10 mm.
9. The mobile electronic device of claim 1 , wherein the Telephoto lens unit comprises multiple lens elements arranged along a lens optical axis and made of at least two different polymer materials having different Abbe numbers, wherein the multiple lens elements comprise a first group of at least three lens elements configured to form a Telephoto lens assembly and a second group of at least two lens elements configured to form a field lens assembly, and wherein the field lens assembly is spaced from the Telephoto lens assembly by a predetermined effective gap.
10. The mobile electronic device of claim 9 , wherein the at least two different polymer materials comprise at least one plastic material with the Abbe number larger than 50, and at least one plastic material with the Abbe number smaller than 30.
11. The mobile electronic device of claim 9 , wherein the TTL T is smaller than 6.2 mm, wherein EFL T is larger than 6.8 mm, and wherein the Telephoto lens unit has an optical diameter larger than 5 mm, thereby enabling to provide an image on an entire area of a ⅓″ image sensor.
12. The mobile electronic device of claim 10 , wherein the first group of lens elements comprises, in order from an object plane to an image plane along an optical axis of the telephoto lens unit, a first lens element having positive optical power and a pair of second and third lens elements having together negative optical power such that the Telephoto lens assembly provides a Telephoto optical effect of the Telephoto lens unit, wherein the second and third lens elements have different Abbe numbers for reducing chromatic aberrations of the Telephoto lens unit, and wherein the second group of at least two lens elements comprises a fourth lens element and a fifth lens element having different Abbe numbers and configured to correct a field curvature of the Telephoto lens assembly and to compensate for residual chromatic aberrations of the Telephoto lens assembly dispersed during light passage through the effective gap.
13. The mobile electronic device of claim 12 , wherein the first, third and fifth lens elements have each an Abbe number greater than 50, and wherein the second and fourth lens elements have each an Abbe number smaller than 30.
14. The mobile electronic device of claim 12 , wherein the predetermined effective gap is equal to or larger than ⅕×TTL T .
15. The mobile electronic device of claim 14 , wherein the lens elements of the field lens assembly are spaced apart of each other by an effective air gap smaller than 1/50×TTL T .
16. The mobile electronic device of claim 15 , wherein TTL T is smaller than 5.5 mm, wherein EFL T is larger than 5.9 mm, and wherein the Telephoto lens unit has an optical diameter larger than 4 mm, thereby enabling to provide an image on an entire area of a ¼″ image sensor.
17. A camera for integrating in a mobile electronic device, the camera comprising a Wide camera unit comprising a Wide lens unit with a field of view FOV W and having a total track length TTL W and an effective focal length EFL W in the range 2.5-6 mm, and a Telephoto camera unit comprising a Telephoto lens unit with a Telephoto field of view FOV T and having a total track length TTL T and an effective focal length EFL T in the range 5-12 mm, wherein the Telephoto lens unit comprises multiple lens elements arranged along a lens optical axis and has a F # smaller than 3.2 and an optical diameter smaller than 5 mm, wherein the TTL T includes a glass window, wherein a ratio TTL W /EFL W is greater than 1, wherein a ratio TTL T /EFL T is smaller than 1.
18. The camera of claim 17 , wherein the multiple lens elements are made of at least two different polymer materials having different Abbe numbers and comprise a first group of at least three lens elements configured to form a Telephoto lens assembly and a second group of at least two lens elements configured to form a field lens assembly, and wherein the field lens assembly is spaced from the Telephoto lens assembly by a predetermined effective gap.
19. The camera of claim 17 , wherein the Wide and Telephoto camera units define separate Wide and Telephoto optical paths and are spaced apart from each other a distance d of about 1 mm.
20. The camera of claim 17 , wherein lens elements of at least the Telephoto lens unit are made of one or more polymer materials.
21. The camera of claim 17 , wherein TTL T is smaller than 5.5 mm, wherein EFL T is larger than 5.9 mm, and wherein the Telephoto lens unit has an optical diameter larger than 4 mm, thereby enabling to provide an image on an entire area of a ¼″ image sensor.
22. The camera of claim 17 , wherein the TTL T is smaller than 6.2 mm, wherein EFL T is larger than 6.8 mm, and wherein the Telephoto lens unit has an optical diameter larger than 5 mm, thereby enabling to provide an image on an entire area of a ⅓″ image sensor.
23. The camera of claim 18 , wherein the first group of lens elements comprises, in order from an object plane to an image plane along an optical axis of the telephoto lens unit, a first lens element having positive optical power and a pair of second and third lens elements having together negative optical power such that the Telephoto lens assembly provides a Telephoto optical effect of the Telephoto lens unit, wherein the second and third lens elements have different Abbe numbers for reducing chromatic aberrations of the Telephoto lens unit, and wherein the second group of at least two lens elements comprises a fourth lens element and a fifth lens element having different Abbe numbers and configured to correct a field curvature of the Telephoto lens assembly and to compensate for residual chromatic aberrations of the Telephoto lens assembly dispersed during light passage through the effective gap.
24. The camera of claim 18 , wherein the predetermined effective gap is equal to or larger than ⅕×TTL T .
25. The camera of claim 18 , wherein the lens elements of the field lens assembly are spaced apart of each other by an effective air gap smaller than 1/50×TTL T .
26. The camera of claim 18 , wherein the at least two different polymer materials comprise at least one plastic material with the Abbe number larger than 50, and at least one plastic material with the Abbe number smaller than 30.
27. The camera of claim 22 , wherein the first, third and fifth lens elements have each an Abbe number greater than 50, and wherein the second and fourth lens elements have each an Abbe number smaller than 30.