CN201017095Y

CN201017095Y - Rear-projection catadioptric object lens

Info

Publication number: CN201017095Y
Application number: CNU2007200896293U
Authority: CN
Inventors: 马永珍; 王海湘; 王天州
Original assignee: LIDA OPTICAL AND ELECTRONIC CO Ltd
Current assignee: LIDA OPTICAL AND ELECTRONIC CO Ltd
Priority date: 2007-03-06
Filing date: 2007-03-06
Publication date: 2008-02-06
Anticipated expiration: 2017-03-06

Abstract

The utility model relates to a back-projection catadioptric object lens mainly comprising a main lens barrel, a focusing ring, a front lens barrel, a back lens barrel, a reflector and a lens combination; the lens combination consists of a front lens group of a single negative lens, a single negative lens, a single negative lens and a doublet lens and a back lens group of a single positive lens, a doublet lens, a doublet lens, a single positive lens, a single positive lens and a reflector; the included angle of the front lens optical axis and the back lens optical axis is 90 degrees and the reflector is equipped at the junction of the two lens group optical axes. The projection object lens is characterized by high resolving capacity, high brightness, little image infidelity, even brightness and clear display. Only a piece of ordinary optical glass is needed for the lens to meet the requirements of good usability and low manufacturing cost which is fit for mass production.

Description

The back projection catadioptric objective

Technical field

The utility model belongs to the video projection field, is a kind of back projection catadioptric objective that uses on the large screen back projection TV that is applicable to.

Background technology

In existing image information technical development field, progress along with the large screen back projection television display technology, require television indicator to develop to giant-screen, high resolving power, multimedia input even interactive direction, therefore, requirement to the rear-projection TV projection objective is very high, the producer of each big production rear-projection TV all wishes to produce good imaging quality, lightweight projection objective, make it can either be applicable to installing and using of large screen back projection TV, can reach high imaging quality, low cost again and satisfy the manufacturability requirement.And existing rear-projection TV projection objective, because of being subjected to the restriction of some performance index, its structure adopts non-spherical lens at the imaging end, causes the big easy deformation of bore, and manufacturability is poor, and the assembling qualification rate is very low, is difficult for producing in batches.

The utility model content

The purpose of this utility model provides a kind of requirement that can satisfy large screen back projection TV high imaging quality, high resolving power, low cost, good manufacturability, and the back projection catadioptric objective that is suitable for producing in enormous quantities.

Realize that the technical scheme that the purpose of this utility model is taked is: this projection objective comprises body tube, focusing ring, preceding lens barrel, back lens barrel, catoptron and combination of lenses, wherein, combination of lenses is the single negative lens by front lens group, single negative lens, single negative lens, cemented doublet, the single-positive-lens of rear lens group, cemented doublet, cemented doublet, single-positive-lens, single-positive-lens and catoptron constitute, first of front lens group, two lens are installed in the preceding lens barrel, and be connected with the body tube suit, the lens of rear lens group are installed in the lens barrel of back, and by being threaded in the other end of body tube, 90 ° each other on front lens group optical axis and rear lens group optical axis, catoptron is positioned at the intersection point place of two lens combination optical axises.

The structural arrangement of front lens group is in the described lens assembly: first single negative lens, have nonreentrant surface in the imaging side, second single negative lens has nonreentrant surface, the 3rd single negative lens has the concave-concave surface in the imaging side, the 4th cemented doublet has nonreentrant surface in the imaging side.

The structural arrangement of rear lens group is in the described lens assembly: the 6th single-positive-lens, has nonreentrant surface in the imaging side, the 7th is cemented doublet, in the imaging side is the plane, and the 8th is cemented doublet, has nonreentrant surface in the imaging side, the 9th for single-positive-lens is, in the imaging side is the plane, and the tenth is single-positive-lens, is nonreentrant surface in the imaging side.

The back projection catadioptric objective of making according to such scheme adopts telecentric beam path in image space, makes the chief ray of emergent light and optical axis included angle≤0.5 °.Compared with prior art, advantages such as these object lens have high resolving power, high brightness, pattern distortion is little, brightness is even, clear display, and also lens only need adopt ordinary optical glass, can satisfy good manufacturability, and cost of manufacture is low, is fit to requirement of mass production.

Description of drawings

Fig. 1 is a structural representation of the present utility model.

Embodiment

Referring to Fig. 1, back projection catadioptric objective of the present utility model, have body tube 13, focusing ring 15, preceding lens barrel 16, back lens barrel 12, catoptron 5 and combination of lenses, wherein combination of lenses is to be made of front lens group, rear lens group and a catoptron 5 of being installed in the body tube 13, and front lens group is arranged with single negative lens 1, single negative lens 2, single negative lens 3 and cemented doublet 4; Rear lens group is arranged with single-positive-lens 6, cemented doublet 7, cemented doublet 8, single-positive-lens 9, single-positive-lens 10.First and second lens of front lens group are installed in the preceding lens barrel 16, preceding lens barrel 16 is connected with body tube 13 suits, the lens of rear lens group are installed in the lens barrel 12 of back, and by being threaded in the other end of body tube 13,90 ° each other on front lens group optical axis and rear lens group optical axis, catoptron 5 is positioned at the intersection point place of two lens combination optical axises, and light sends through catoptron change direction from rear lens group and projects image from front lens group.The structural arrangement of front lens group is: first single negative lens, have nonreentrant surface in the imaging side, and second single negative lens has nonreentrant surface, the 3rd single negative lens has the concave-concave surface in the imaging side, and the 4th cemented doublet has nonreentrant surface in the imaging side.The structural arrangement of rear lens group is: the 6th single-positive-lens, has nonreentrant surface in the imaging side, the 7th is cemented doublet, in the imaging side is the plane, and the 8th is cemented doublet, has nonreentrant surface in the imaging side, the 9th for single-positive-lens is, in the imaging side is the plane, and the tenth is single-positive-lens, is nonreentrant surface in the imaging side.Spacing distance between each lens is: the airspace between

lens

1 and 2 lens is 11.67mm, airspace between lens 2 and the lens 3 is 20.77mm, airspace between lens 3 and the cemented doublet 4 is 19.31mm, airspace between cemented doublet 4 and the catoptron 5 is 39mm, airspace between catoptron 5 and the lens 6 is 19.5+11.94mm, airspace between lens 6 and the cemented doublet 7 is 0.82mm, airspace between cemented doublet 7 and the balsaming lens 8 is 0.82mm, airspace between cemented doublet 8 and the lens 9 is 0.25mm, and the airspace between lens 9 and the lens 10 is 0.2mm.

In front lens, lens 1 and lens 2 are the focusing group, be installed in the preceding lens barrel 16, its outside is provided with focusing ring 15, and be connected with body tube 13 by screw thread, can be by rotating focusing ring 15 airspaces of regulating between lens 2 and the lens 3, the rigging error of bringing with bucking-out system lens and part processing, thus guarantee that image planes focusing is clear.Label 11 is outer trim rings, is used for fixing back lens barrel 12, and label 14 is the mirror holder of stationary mirror 5, and label 17 is lens cases.

Claims

1. back projection catadioptric objective, comprise body tube, focusing ring, preceding lens barrel, back lens barrel, catoptron and combination of lenses, it is characterized in that: combination of lenses is the single negative lens by front lens group, single negative lens, single negative lens, cemented doublet, the single-positive-lens of rear lens group, cemented doublet, cemented doublet, single-positive-lens, single-positive-lens and catoptron constitute, wherein, first of front lens group, two lens are installed in the preceding lens barrel, and be connected with the body tube suit, the lens of rear lens group are installed in the lens barrel of back, and by being threaded in the other end of body tube, 90 ° each other on front lens group optical axis and rear lens group optical axis, catoptron is positioned at the intersection point place of two lens combination optical axises.

2. back projection catadioptric objective according to claim 1, it is characterized in that: being arranged as of described front lens group: first is sphere list negative lens, has nonreentrant surface in the imaging side, second is plastic aspherical element list negative lens, have in the imaging side nonreentrant surface, the 3rd for single negative lens, have the concave-concave surface, the 4th is cemented doublet, has the biconvex surface.

3. back projection catadioptric objective according to claim 1 and 2, it is characterized in that: the airspace between described front lens group first lens and second lens is 11.67mm, airspace between second lens and the 3rd lens is 20.77mm, and the airspace between the 3rd lens and the 4th lens is 19.31mm.

4. back projection catadioptric objective according to claim 1, it is characterized in that: being arranged as of described rear lens group: the 6th is single-positive-lens, have convex surface in the imaging side, the 7th is cemented doublet, has convex surface in the imaging side, the 8th is cemented doublet, have the biconvex surface, the 9th is single-positive-lens, has nonreentrant surface in the imaging side, the tenth is single-positive-lens, has the biconvex surface.

5. according to claim 1 or 4 described back projection catadioptric objectives, it is characterized in that: the airspace between described rear lens group the 6th lens and the 7th lens is 0.82mm, airspace between the 7th lens and the 8th lens is 0.82mm, airspace between the 8th lens and the 9th lens is 0.25mm, airspace between the 9th lens and the tenth lens is 0.2mm, airspace between the tenth lens and the prism is 3mm, and the airspace between prism and the chip is 3.4mm.