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 EFL W =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 EFL T =5-12 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, and wherein the Telephoto lens unit has an optical axis and an optical diameter smaller than 5 mm and a F #smaller than 3.2 and includes a first group of at least three lens elements having, in order from an object plane to an image plane along the optical axis, a first lens element having positive optical power and a pair of second and third lens elements having together negative optical power, and a second group of at least two lens elements, wherein each of the at least two lens elements in the second group is made of different polymer materials having different Abbe numbers.
2. The mobile electronic device of claim 1 , wherein the at least two lens elements of the second group are spaced from one another by an effective air gap smaller than TTL T /50.
3. The mobile electronic device of claim 1 , wherein the Wide and Telephoto camera units are spaced from one another a distance of about 1 mm.
4. The mobile electronic device of claim 1 , wherein TTL T is smaller than 5.5 mm.
5. The mobile electronic device of claim 1 , wherein the first lens element of the Telephoto lens unit has a focal length f 1 smaller than TTL T /2.
6. The mobile electronic device of claim 1 , wherein the first, second and third lens elements have respective focal lengths f 1 , f 2 and f 3 , and wherein the respective focal lengths satisfy the condition 1.2|f 3 |>|f 2 |>1.5f 1 .
7. The mobile electronic device of claim 1 , wherein the Telephoto camera unit includes an image sensor with an image sensor size ¼″ to ⅓″.
8. The mobile electronic device of claim 2 , wherein the Wide and Telephoto camera units are spaced from one another a distance of about 1 mm.
9. The mobile electronic device of claim 2 , wherein TTL T is smaller than 5.5 mm.
10. The mobile electronic device of claim 2 , wherein the first lens element of the Telephoto lens unit has a focal length f 1 smaller than TTL T /2.
11. A 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 , a total track length TTL T and an effective focal length EFL T in the range 5-12 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, and wherein the Telephoto lens unit has an optical axis and an optical diameter smaller than 5 mm and a F #smaller than 3.2 and includes a first group of at least three lens elements having, in order from an object plane to an image plane along the optical axis, a first lens element having positive optical power and a pair of second and third lens elements having together negative optical power, and a second group of at least two lens elements, wherein each of the at least two lens elements in the second group is made of the different polymer materials.
12. The camera of claim 11 , wherein the at least two lens elements of the second group are spaced from one another by an effective air gap smaller than TTL T /50.
13. The camera of claim 11 , wherein the Wide and Telephoto camera units are spaced from one another a distance of about 1 mm.
14. The camera of claim 11 , wherein TTL T is smaller than 5.5 mm.
15. The camera of claim 11 , wherein the first lens element of the Telephoto lens unit has a focal length f 1 smaller than TTL T /2.
16. The camera of claim 11 , wherein the first, second and third lens elements have respective focal lengths f 1 , f 2 and f 3 , and wherein the respective focal lengths satisfy the condition 1.2|f 3 |>|f 2 |>1.5f 1 .
17. The camera of claim 11 , wherein the Telephoto camera unit includes an image sensor with an image sensor size ¼″ to ⅓″.
18. The camera of claim 12 , wherein the first lens element of the Telephoto lens unit has a focal length f 1 smaller than TTL T /2.
19. The camera of claim 12 , wherein the first, second and third lens elements have respective focal lengths f 1 , f 2 and f 3 , and wherein the respective focal lengths satisfy the condition 1.2|f 3 |>|f 2 |>1.5f 1 .
20. The camera of claim 12 , wherein the Telephoto camera unit includes an image sensor with an image sensor size ¼″ to ⅓″.