CN104516091A - High-low temperature infrared confocal optical system with high resolution and low cost - Google Patents

Abstract

The invention relates to a high-low temperature infrared confocal optical system with high resolution and low cost. The high-low temperature infrared confocal optical system is characterized by comprising a first lens (1), a second lens (2), a diaphragm (3), a third lens (4), a fourth lens (5), an optical filter (6), a piece of protective glass (7) and a light-sensitive chip (8), which are sequentially arranged, wherein the first lens (1), the second lens (2), the third lens (3) and the fourth lens (4) are all plastic aspheric surface lenses. The high-low temperature infrared confocal optical system with the high resolution and the low cost solves the high-low temperature and infrared focus deflecting problems and realizes the image quality consistency under different environments.

Description

A kind of high/low temperature, infrared confocal, high pixel, low-cost optical system

[technical field]

The present invention relates to a kind of high/low temperature, infrared confocal, high pixel, low-cost optical system.

[background technology]

The shortcoming that current monitoring camera camera lens used ubiquity is such: camera lens high/low temperature, infrared not confocal, high in cost of production, only has now minority camera lens, improve in certain when sacrificing other side, such as in order to realize high/low temperature, infrared confocal and high pixel, just employ Glass aspheric eyeglass, improve cost, the demand of consumer's low cost can not be met.

In order to solve above-mentioned existing problem, the present invention makes useful improvement.

[summary of the invention]

Technical matters to be solved by this invention is for above-mentioned deficiency of the prior art, a kind of high/low temperature, infrared confocal, high pixel, low-cost optical system are provided, this high/low temperature, infrared confocal, high pixel, low-cost optical system well solve high/low temperature, the burnt problem of infrared race, realize the consistance of picture element in varying environment.

For achieving the above object, present invention employs following technical proposals:

A kind of high/low temperature, infrared confocal, high pixel, low-cost optical system; comprise the first eyeglass, the second eyeglass, diaphragm, the 3rd eyeglass, the 4th eyeglass, optical filter, cover glass and the sensitive chip that arrange in turn, described first eyeglass, the second eyeglass, the 3rd eyeglass and the 4th eyeglass are plastic aspherical element eyeglass.

The focal length of the first eyeglass described above, the 4th eyeglass is negative, and the focal length of described second eyeglass, the 3rd eyeglass is just.

The aspheric surface face type of the first eyeglass described above, the second eyeglass, the 3rd eyeglass and the 4th eyeglass meets equation: $Z={\mathrm{cy}}^2/\{1+\sqrt{[1-(1+k)c2y2]}\}+{\mathrm{\α}}_1{y}^2+{\mathrm{\α}}_2{y}^4+{\mathrm{\α}}_3{y}^6+{\mathrm{\α}}_4{y}^8+{\mathrm{\α}}_5{y}^{10}+{\mathrm{\α}}_6{y}^{12}+{\mathrm{\α}}_7{y}^{14}+{\mathrm{\α}}_8{y}^{16},$ In formula, the curvature of parameter c corresponding to radius, y is radial coordinate (its unit is identical with length of lens unit), and k is circular cone whose conic coefficient; When k-factor is less than-1, the face shape curve of lens is hyperbolic curve, and when k-factor equals-1, the face shape curve of lens is para-curve; When k-factor is between-1 to 0, the face shape curve of lens is oval, and when k-factor equals 0, the face shape curve of lens is circular, and when k-factor is greater than 0, the face shape curve of lens is oblate; α ₁to α ₈represent the coefficient corresponding to each radial coordinate respectively.

The invention has the beneficial effects as follows:

1, existing high pixel monitoring camera generally adopts glass sphere or Glass aspheric eyeglass, and the present invention adopts all-plastic aspheric surface, and cost significantly reduces.

2, the periphery resolution of existing high pixel monitoring camera is lower, and the present invention can blur-free imaging at whole picture.

3, existing high pixel monitoring camera is easily unbalance on image sharpness and color reducibility, and this camera lens adopts wide spectral 1:1:1 design, has fabulous image sharpness and color reducibility at visible light wave range.

4, existing high pixel monitoring camera high/low temperature, infrared on can not realize confocal, to well defocused under generation white light normal temperature, occur that serious race is burnt under high/low temperature and infrared environmental, the situation that image planes are fuzzy. the present invention well solves high/low temperature, the burnt problem of infrared race, realizes the consistance of picture element in varying environment.

[accompanying drawing explanation]

Fig. 1 is schematic diagram of the present invention.

[embodiment]

Below in conjunction with accompanying drawing, further detailed description is done to the present invention.

As shown in Figure 1, a kind of high/low temperature, high/low temperature, infrared confocal, high/low temperature, infrared confocal, high pixel, low-cost optical system, comprise the first eyeglass 1 arranged in turn, second eyeglass 2, diaphragm 3, 3rd eyeglass 4, 4th eyeglass 5, optical filter 6, cover glass 7 and sensitive chip 8, described first eyeglass 1, second eyeglass 2, 3rd eyeglass 4 and the 4th eyeglass 5 are plastic aspherical element eyeglass, this high/low temperature, infrared confocal, high pixel, low-cost optical system well solves high/low temperature, the burnt problem of infrared race, realize the consistance of picture element in varying environment, the present invention adopts all-plastic aspheric surface, cost significantly reduces, the present invention can blur-free imaging at whole picture, this camera lens adopts wide spectral 1:1:1 design, fabulous image sharpness and color reducibility is had at visible light wave range.

As shown in Figure 1, in the present embodiment, the focal length of described first eyeglass 1, the 4th eyeglass 5 is negative, the focal length of described second eyeglass 2, the 3rd eyeglass 4 is just, the present invention can blur-free imaging at whole picture, this camera lens adopts wide spectral 1:1:1 design, has fabulous image sharpness and color reducibility at visible light wave range.

As shown in Figure 1, in the present embodiment, the aspheric surface face type of described first eyeglass 1, second eyeglass 2, the 3rd eyeglass 4 and the 4th eyeglass 5 meets equation: $Z={\mathrm{cy}}^2/\{1+\sqrt{[1-(1+k)c2y2]}\}+{\mathrm{\α}}_1{y}^2+$ ${\mathrm{\α}}_2{y}^4+{\mathrm{\α}}_3{y}^6+{\mathrm{\α}}_4{y}^8+{\mathrm{\α}}_5{y}^{10}+{\mathrm{\α}}_6{y}^{12}+{\mathrm{\α}}_7{y}^{14}+{\mathrm{\α}}_8{y}^{16},$ In formula, the curvature of parameter c corresponding to radius, y is that its unit of radial coordinate is identical with length of lens unit, and k is circular cone whose conic coefficient; When k-factor is less than-1, the face shape curve of lens is hyperbolic curve, and when k-factor equals-1, the face shape curve of lens is para-curve; When k-factor is between-1 to 0, the face shape curve of lens is oval, and when k-factor equals 0, the face shape curve of lens is circular, and when k-factor is greater than 0, the face shape curve of lens is oblate; α ₁to α ₈represent the coefficient corresponding to each radial coordinate respectively.

High/low temperature is confocal to be realized mainly through following methods: the expansion coefficient that adopts different plastic materials corresponding is different, and bamboo product goes out different face types, and when making high/low temperature, face type produces complementary, thus high/low temperature time image matter is remained unchanged.

Infraredly confocally to realize mainly through following methods: different plastic refractive index Nd, the Abbe number Vd value of reasonable distribution, by reasonable in design type, make camera lens meet the imaging clearly of Infrared under to white light imaging clearly prerequisite simultaneously.

Its high pixel realizes mainly through following approach: 1. high efficiency material adapted, positive and negative according to each lens, reasonably distributes refractive index Nd and Abbe number Vd value, is selecting suitable material according to this; 2., while during design, emphasis promotes center resolution, the aberration correction of pay abundant attention surrounding visual field, ensures that whole picture image quality is even; 3. adopt wide spectral 1:1:1 design, thus ensure that high-quality image sharpness and color reducibility.

Sensitive chip 8 is provided with below at the 4th eyeglass 5; insert optical filter 6 at the 4th piece between eyeglass 5 and sensitive chip 8 simultaneously; cover glass 7; to filter the veiling glare outside design wave band; and when designing; the aberration that the backing material considering optical filter 6 and cover glass 7 is introduced, is corrected, is realized best imaging effect.

Confocal at the temperature of high temperature (about 60 degree) and low temperature (about subzero 30 degree); Also be confocal under visible ray and infrared light state.

Here is actual design case of the present invention:

Face is numbered	Face type	Radius R	Thickness	Material	Effective diameter
						OBJ	Standard sphere	INFINITY	INFINITY	AIR	INFINITY
S1	Even number aspheric surface	-22.2	1.201	F52R	9.25
						S2	Even number aspheric surface	4	2.1	AIR	5.71
S3	Even number aspheric surface	-8.912	3.83	SP1516	5.7
						S4	Even number aspheric surface	-8	3.9	AIR	4.9
Diaphragm	Standard sphere	INFINITY	2.1	AIR	2.55
						S5	Even number aspheric surface	5	2.76	F52R	3
S6	Even number aspheric surface	-2.03	0.5	AIR	3
						S7	Even number aspheric surface	-1.7	0.6	OKP1	2.9
S8	Even number aspheric surface	-3.5	0.5	AIR	2.9
						S9	Standard sphere	INFINITY	0.3	K9L	3.1
S10	Standard sphere	INFINITY	0.4	AIR	3.2
						S11	Standard sphere	INFINITY	0.5	K9L	3.3
S12	Standard sphere	INFINITY	4.1	AIR	3.5
						Image planes	Standard sphere	INFINITY			4.7

As above among form, two faces of corresponding first eyeglass 1 of S1, S2, two faces of corresponding second eyeglass 2 of S3, S4; two faces of corresponding 3rd eyeglass 4 of S5, S6, two faces of corresponding 4th eyeglass 5 of S7, S8; two faces of the corresponding optical filter 6 of S9, S10, two faces of the corresponding cover glass of S11, S12.

The asphericity coefficient in each face:

	k	a 2	a 3	a 4	a 5
						S1	-1.5	-4E-004	8.2E-005	-4E-006	8.5E-008
S2	-2	5E-003	-2E-003	6.8E-004	0
						S3	8	3.7E-004	8.06E-005	-4E-005	-6.5E-007
S4	-1.3	-5.3E-004	-1.7E-004	6.6E-006	-9E-007
						S5	-0.25	-5E-004	-9E-003	7.65E-003	-7.23E-003
S6	-0.86	-4E-004	-8.351E-005	2.485E-003	7.005E-004
						S7	-1.4	8.03E-003	5.23E-003	-5.481E-005	-6.5E-004
S8	-2.6	9.643E-003	7.523E-004	4.315E-005	-4.015E-004

As above among form, two faces of corresponding first eyeglass 1 of S1, S2, two faces of corresponding second eyeglass 2 of S3, S4, two faces of corresponding 3rd eyeglass 4 of S5, S6, two faces of corresponding 4th eyeglass 5 of S7, S8.

Claims (3)

1. a high/low temperature, infrared confocal, high pixel, low-cost optical system; it is characterized in that: comprise the first eyeglass (1), the second eyeglass (2), diaphragm (3), the 3rd eyeglass (4), the 4th eyeglass (5), optical filter (6), cover glass (7) and the sensitive chip (8) that arrange in turn, described first eyeglass (1), the second eyeglass (2), the 3rd eyeglass (4) and the 4th eyeglass (5) are plastic aspherical element eyeglass.

2. high/low temperature according to claim 1, infrared confocal, high pixel, low-cost optical system, it is characterized in that: the focal length of described first eyeglass (1), the 4th eyeglass (5) is negative, the focal length of described second eyeglass (2), the 3rd eyeglass (4) is just.

3. high/low temperature according to claim 1 and 2, infrared confocal, high pixel, low-cost optical system, is characterized in that: the aspheric surface face type of described first eyeglass (1), the second eyeglass (2), the 3rd eyeglass (4) and the 4th eyeglass (5) meets equation: $Z={\mathrm{cy}}^2/\{1+\sqrt{[1-(1+k)c2y2]}\}+\mathrm{\α}$ $y_2^1+{\mathrm{\α}}_2{y}^4+{\mathrm{\α}}_3{y}^6+{\mathrm{\α}}_4{y}^8+{\mathrm{\α}}_5{y}^{10}+{\mathrm{\α}}_6{y}^{12}+{\mathrm{\α}}_7{y}^{14}+{\mathrm{\α}}_8{y}^{16},$ In formula, the curvature of parameter c corresponding to radius, y is radial coordinate (its unit is identical with length of lens unit), and k is circular cone whose conic coefficient; When k-factor is less than-1, the face shape curve of lens is hyperbolic curve, and when k-factor equals-1, the face shape curve of lens is para-curve; When k-factor is between-1 to 0, the face shape curve of lens is oval, and when k-factor equals 0, the face shape curve of lens is circular, and when k-factor is greater than 0, the face shape curve of lens is oblate; α ₁to α ₈represent the coefficient corresponding to each radial coordinate respectively.