TW200712591A - Projection lens with fixed focal length - Google Patents

Projection lens with fixed focal length

Info

Publication number
TW200712591A
TW200712591A TW094132014A TW94132014A TW200712591A TW 200712591 A TW200712591 A TW 200712591A TW 094132014 A TW094132014 A TW 094132014A TW 94132014 A TW94132014 A TW 94132014A TW 200712591 A TW200712591 A TW 200712591A
Authority
TW
Taiwan
Prior art keywords
focal length
lens group
projection lens
lens
projection
Prior art date
Application number
TW094132014A
Other languages
Chinese (zh)
Other versions
TWI268381B (en
Inventor
Chung-Yuan Kuo
Original Assignee
Asia Optical Co Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Asia Optical Co Inc filed Critical Asia Optical Co Inc
Priority to TW094132014A priority Critical patent/TWI268381B/en
Application granted granted Critical
Publication of TWI268381B publication Critical patent/TWI268381B/en
Publication of TW200712591A publication Critical patent/TW200712591A/en

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Abstract

The invention provides a projection lens with fixed focal length. The projection lens includes a first lens group with negative optical power and a second lens group with positive optical power in sequence from the enlarging side to the reducing side. When the distance between the projection screen and the projection lens is varied, the first lens group is moved to obtain a good image on the screen, meanwhile, the distance between the second lens group and the display element is fixed. The projection lens satisfies the following condition: wherem f1 is the focal length of the first lens group and f2 is the focal length of the second lens group.
TW094132014A 2005-09-16 2005-09-16 Projection lens with fixed focal length TWI268381B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
TW094132014A TWI268381B (en) 2005-09-16 2005-09-16 Projection lens with fixed focal length

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
TW094132014A TWI268381B (en) 2005-09-16 2005-09-16 Projection lens with fixed focal length

Publications (2)

Publication Number Publication Date
TWI268381B TWI268381B (en) 2006-12-11
TW200712591A true TW200712591A (en) 2007-04-01

Family

ID=57911298

Family Applications (1)

Application Number Title Priority Date Filing Date
TW094132014A TWI268381B (en) 2005-09-16 2005-09-16 Projection lens with fixed focal length

Country Status (1)

Country Link
TW (1) TWI268381B (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TWI503566B (en) 2013-10-31 2015-10-11 玉晶光電股份有限公司 An optical imaging lens and an electronic device to which the optical imaging lens is applied
TWI484247B (en) 2013-12-20 2015-05-11 玉晶光電股份有限公司 Camera device and optical imaging lens thereof
TWI477808B (en) * 2014-01-17 2015-03-21 Largan Precision Co Ltd Image capturing lens assembly, image capturing device and automobile photographing terminal

Also Published As

Publication number Publication date
TWI268381B (en) 2006-12-11

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Legal Events

Date Code Title Description
MM4A Annulment or lapse of patent due to non-payment of fees