US 11,714,261 B2
Wide-angle lens assembly
Yuan-Fan Liang, Taichung (TW)
Assigned to SINTAI OPTICAL (SHENZHEN) CO., LTD., Shenzhen (CN); and ASIA OPTICAL CO., INC., Taichung (TW)
Filed by Sintai Optical (Shenzhen) Co., Ltd., ShenZhen (CN); and Asia Optical Co., Inc., Taichung (TW)
Filed on Apr. 10, 2020, as Appl. No. 16/845,162.
Claims priority of application No. 201910293468.7 (CN), filed on Apr. 12, 2019.
Prior Publication US 2020/0326515 A1, Oct. 15, 2020
Int. Cl. G02B 9/60 (2006.01); G02B 13/06 (2006.01); G02B 13/18 (2006.01); G02B 9/62 (2006.01)
CPC G02B 9/60 (2013.01) [G02B 9/62 (2013.01); G02B 13/06 (2013.01); G02B 13/18 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A wide-angle lens assembly comprising:
a first lens group with negative refractive power;
a second lens group with negative refractive power;
a third lens group with positive refractive power;
a fourth lens group with positive refractive power; and
a fifth lens group with positive refractive power;
wherein the first lens group comprises a first lens, the second lens group comprises a second lens, the third lens group comprises a third lens;
wherein the first lens group, the second lens group, the third lens group, the fourth lens group and the fifth lens group are arranged in order from an object side to an image side along an optical axis;
wherein the fourth lens group comprises a sixth lens;
wherein the sixth lens comprises a concave surface facing the object side and another concave surface facing the image side;
wherein the wide-angle lens assembly satisfies:
0.5<|fLG4/fLG5|<1.8,
where fLG4 is an effective focal length of the fourth lens group, and fLG5 is an effective focal length of the fifth lens group;
wherein the wide-angle lens assembly satisfies at least one of following conditions:
TTL/f<11;
19<TTL/T1<24;
−3.4<fLG1/f<LG2/f<fLG3/f<3.8;
where TTL is a distance between an object side surface of the first lens and an image plane along the optical axis, f is an effective focal length of the wide-angle lens assembly, T1 is a thickness of the first lens along the optical axis, fLG1 is an effective focal length of the first lens group, fLG2 is an effective focal length of the second lens group, and fLG3 is an effective focal length of the third lens group.