Summary of the invention
The invention provides a kind of method that eyeglass stress detects, it is not quick that its object is to solve eyeglass stress test process, the problem that stress testing result cannot quantize; Another object of the present invention is to solve eyeglass, in stress testing process, center of lens near zone is often used to the problem of region institute affected by force size because of the eyeglass that cannot judge that inconvenient subregion causes.
Technical scheme of the present invention is such:
An eyeglass stress detection method, comprises the steps:
In light path, set gradually area source, the first circuit polarizer, the second circuit polarizer, imaging len and imaging photosensitive element, and described imaging photosensitive element is connected with computing machine;
The center of eyeglass is arranged in the light path between described the first circuit polarizer and the second circuit polarizer, and described light source becomes circularly polarized light after the first circuit polarizer; Described circularly polarized light, after described eyeglass, carries the polarization information of described eyeglass, becomes elliptical polarized light; Described elliptical polarized light, after the second circuit polarizer, is accepted and is converged on described imaging photosensitive element by described imaging len; Described imaging photosensitive element is transferred to computing machine by the polarization information of described eyeglass; Described computing machine quantizes and analyzes the polarization information of described eyeglass, obtains characterizing the stress envelope of described eyeglass affected by force size.
Further: described computing machine quantizes and analyzes described polarization information, the concrete steps that obtain characterizing the stress envelope of described eyeglass affected by force size comprise:
Described stress envelope is divided into N region, and wherein M areal distribution has i pixel, and the pixel value of j pixel in a described i pixel is X
mj; Wherein, N=4K+1, K is 0 and natural number; M, i and j are natural number;
Calculate brightness average and the brightness variance yields of M the pixel of the i in region,
Brightness average:
Brightness variance yields:
According to described brightness average
with described brightness variance yields S
m 2, symbolize the size of M region institute affected by force of described eyeglass.
Further: described according to described brightness average
with described brightness variance yields S
m 2, the concrete determination step that symbolizes M region institute affected by force size of described eyeglass is:
If the first brightness average that M region of eyeglass records before eyeglass assembling or processing is
the first brightness variance yields is S
m1 2; The the second brightness average recording after assembling or processing is
the second brightness variance yields is S
m2 2;
When the first circuit polarizer is that Left-hand circular polarization device, the second circuit polarizer are that right-hand circular polarization device or the first circuit polarizer are that right-hand circular polarization device, the second circuit polarizer are Left-hand circular polarization device or when the first circuit polarizer and the second circuit polarizer are Left-hand circular polarization device or are right-hand circular polarization device
If there is not light and dark striped in M region of eyeglass, by comparing the first brightness average
with the second brightness average
judge the size of M region institute affected by force of eyeglass;
If there is light and dark striped in M region of eyeglass, by comparing the first brightness variance yields S
m1 2with the second brightness variance yields S
m2 2judge the size of M region institute affected by force of eyeglass.
Further: when described the first circuit polarizer is that Left-hand circular polarization device, the second circuit polarizer are that right-hand circular polarization device or the first circuit polarizer are right-hand circular polarization device, the second circuit polarizer while being Left-hand circular polarization device,
If there is not light and dark striped in M region of eyeglass, by comparing the first brightness average
with the second brightness average
judge eyeglass M region institute affected by force big or small concrete decision method as:
If
show that M region of eyeglass affected by force after assembling or processing becomes large;
If
show that M region of eyeglass affected by force after assembling or processing is constant;
If
show that M region of eyeglass affected by force after assembling or processing diminishes;
If there is light and dark striped in M region of eyeglass, by comparing the first brightness variance yields S
m1 2with the second brightness variance yields S
m2 2judge eyeglass M region institute affected by force big or small concrete decision method as:
If S
m2 2>S
m1 2, show that M region of eyeglass affected by force after assembling or processing becomes large; If S
m2 2=S
m1 2, show that M region of eyeglass affected by force after assembling or processing is constant; If S
m2 2<S
m1 2, show that M region of eyeglass affected by force after assembling or processing diminishes.
Further: when the first circuit polarizer and the second circuit polarizer are Left-hand circular polarization device or are right-hand circular polarization device,
If there is not light and dark striped in M region of eyeglass, by comparing the first brightness average
with the second brightness average
size judge eyeglass M region institute affected by force big or small concrete decision method as:
If
show that M region of eyeglass affected by force after assembling or processing diminishes;
If
show that M region of eyeglass affected by force after assembling or processing is constant;
If
show that M region of eyeglass affected by force after assembling or processing becomes large;
If there is light and dark striped in M region of eyeglass, by comparing the first brightness variance yields S
m1 2with the second brightness variance yields S
m2 2size judge eyeglass M region institute affected by force big or small concrete decision method as:
If S
m2 2>S
m1 2, show that M region of eyeglass affected by force after assembling or processing becomes large;
If S
m2 2=S
m1 2, show that M region of eyeglass affected by force after assembling or processing is constant;
If S
m2 2<S
m1 2, show that M region of eyeglass affected by force after assembling or processing diminishes.
Further: described N is 9, and the division methods in its 9 regions is:
Take described center of lens as the center of circle, on described stress envelope, with the first diameter, Second bobbin diameter and the 3rd diameter, mark off from inside to outside the first border circular areas, the second border circular areas and the 3rd border circular areas respectively;
Becoming respectively with horizontal line ± two straight lines of 45 ° are divided into 4 regions separately by described the second border circular areas and described the 3rd border circular areas.
Further: described the first diameter, Second bobbin diameter and the 3rd diameter are followed successively by φ 6mm, φ 12mm and φ 18mm.
Further: described the first diameter, Second bobbin diameter and the 3rd diameter are followed successively by φ 2.5mm, φ 5mm and φ 7.5mm.
Further: by the first border circular areas called after first area, described first area is human eye region corresponding to eyeglass while facing the place ahead; By part the second border circular areas in the right, first area and part the 3rd border circular areas successively called after the 3rd region and SECTOR-SEVEN territory, described the 3rd region and SECTOR-SEVEN territory region corresponding to the corresponding right apparent time eyeglass of human eye; By in the left side, first area by the second border circular areas of described two line segmentations and the 3rd border circular areas successively called after the 5th region and the 9th region, described the 5th region and the 9th region are region corresponding to the left apparent time eyeglass of human eye; By in top, first area by the second border circular areas of described two line segmentations and the 3rd border circular areas successively called after second area and the 6th region, described second area and the 6th region are human eye region corresponding to eyeglass while looking up; By following in first area by the second border circular areas of described two line segmentations and the 3rd border circular areas successively called after the 4th region and Section Eight territory, region corresponding to eyeglass when the corresponding human eye in described the 4th region and Section Eight territory is overlooked.
Further: described area source is uniform area light source.
Beneficial effect of the present invention: Computer display eyeglass stress envelope, this stress envelope is divided into some regions according to people to the use habit of eyeglass, by calculating brightness average and the brightness variance yields of some pixel values in arbitrary region of eyeglass, characterize the size of the selection area institute affected by force of this eyeglass, for the detection of eyeglass stress provides important reference frame.Meanwhile, also can by the brightness average of the different selection area stress of eyeglass relatively or the comparison of brightness variance yields, judge the size of the different selection area of eyeglass institute affected by force.
figure of description
Fig. 1 is eyeglass stress detection method;
Fig. 2 is light channel structure figure of the present invention;
Fig. 3 is that eyeglass stress distribution nine district figure divide schematic diagram;
Fig. 4 is human eye and glasses relative size schematic diagram.
In figure, sequence number and title that each part is corresponding are respectively: 101, area source; 102, the first circuit polarizer; 103, the second circuit polarizer; 104, imaging len; 105, imaging photosensitive element; 201, macular area; 202, eye cornea; 203, eyeglass.
Embodiment
In order to make technical matters to be solved by this invention, technical scheme and beneficial effect clearer, below in conjunction with drawings and Examples, the present invention is further elaborated.Should be appreciated that specific embodiment described herein, only in order to explain the present invention, is not intended to limit the present invention.
With reference to figure 1, eyeglass stress detection method of the present invention is as follows:
In light path, set gradually uniform area light source, the first circuit polarizer, the second circuit polarizer, imaging len and imaging photosensitive element, and described imaging photosensitive element is connected with computing machine;
The center of eyeglass is arranged in the light path between described the first circuit polarizer and the second circuit polarizer, and described area source becomes circularly polarized light after the first circuit polarizer; Described circularly polarized light, after described eyeglass, carries the polarization information of described eyeglass, becomes elliptical polarized light; Described elliptical polarized light, after the second circuit polarizer, converges on described imaging photosensitive element through described imaging len; Described imaging photosensitive element is transferred to computing machine by the polarization information of described eyeglass; Described computing machine quantizes and analyzes the polarization information of described eyeglass, and the sign that obtains described eyeglass to be measured has the stress envelope of stress intensity.
Particularly, with reference to figure 2, uniform area light source 101 is arranged on the bottom of glasses measuring stress instrument (not shown), is disposed with the first circuit polarizer 102, the second circuit polarizers 103, imaging len 104 and imaging photosensitive element 105 on uniform area light source 101.With reference to figure 3, the eyeglass 203 center that need to do stress detection is placed in the light path between the first circuit polarizer 102 and the second circuit polarizer 103.Particularly, a panel (not shown) that first eyeglass should be placed on to glasses measuring stress instrument is upper, and this panel, between the first circuit polarizer 102 and the second circuit polarizer 103, is then adjusted to the center of eyeglass and optical axis coincidence.When light that uniform area light source 101 sends is after the first circuit polarizer 102, become circularly polarized light, after circularly polarized light transmission eyeglass, carry the polarization information of eyeglass, become elliptically polarized light.Elliptically polarized light, after the second circuit polarizer 103, sees through imaging len 104, then converges on imaging photosensitive element 105.Imaging photosensitive element 105 is transferred to the polarization information of eyeglass in the computing machine (not shown) being connected with imaging photosensitive element 105, computing machine utilizes the polarization information analysis of software to eyeglass, obtain the stress envelope of eyeglass, and show the size that characterizes eyeglass institute affected by force.By this detection method, can observe simply, intuitively, efficiently the distribution situation of eyeglass stress, these relative values can be reacted the relative size of the suffered stress influence of eyeglass, and this detection for eyeglass stress provides reference.
At the first circuit polarizer 102, be Left-hand circular polarization sheet or right-hand circular polarization sheet, the second circuit polarizer 103 is in the situation of right-hand circular polarization sheet or Left-hand circular polarization sheet, if there is not stress in lens, lens can not change the polarization state through the circularly polarized light of the first circuit polarizer 102 outgoing, but this is a kind of perfect condition, in fact, even if lens does not have external carbuncle, because eyeglass material exists internal stress and causes eyeglass to have internal stress yet.If introducing external carbuncle, and make external carbuncle large from little change, when external carbuncle hour, it is also less that lens changes polarisation of light degree ability, the stress envelope image that imaging photosensitive element 105 obtains lenses is by secretly brightening.Computing machine is divided into some regions to the stress distribution image of eyeglass according to region partitioning method, calculates brightness average and the brightness variance size of pixel in each region, according to result of calculation, symbolizes lens in the size of this region institute affected by force.
At the first circuit polarizer 102 and the second circuit polarizer 103, be all Left-hand circular polarization device or be all in right-hand circular polarization device situation, in the process increasing gradually at eyeglass stress, the stress envelope image of the eyeglass that imaging photosensitive element 105 obtains will be by bright dimmed.But still can, by brightness average and the brightness variance yields of pixel in each region in calculating eyeglass stress envelope, characterize glasses selection area institute affected by force size.Now the brightness average of pixel is less or brightness variance yields is larger in selection area, and the lens institute affected by force of corresponding region is larger.Along with the continuous increase of stress, the stress envelope image of the eyeglass that imaging photosensitive element 105 obtains also there will be light and dark striped.The stress envelope image that obtains lens according to imaging photosensitive element 105, computing machine calculates brightness average and the brightness variance yields of pixel in each region of eyeglass, characterizes the size of this selection area institute affected by force of glasses.By the method, for detecting, the stress of eyeglass provides important reference.
Above-mentioned middle eyeglass exists the detection method of stress relevant with eyeglass lens measurement area size, eyeglass lens measurement position, thereby is necessary to select the often eyeglass lens measurement region of use, contributes to the detection of the stress of the crucial lens area of using of human eye.
The method that obtains eyeglass stress envelope has multiple, but its principle is basic identical.Before said, the present invention has announced to utilize and has asked the average of pixel and the method for variance to characterize the method for eyeglass selection area institute affected by force size.Lower mask body is set forth size how to utilize average and variance to calculate the eyeglass institute affected by force in each region in eyeglass stress envelope.
Particularly, eyeglass stress envelope is divided into N region, wherein there is i pixel in M region, and j pixel value in a described i pixel is X
mj; Wherein, N=4K+1, K is 0 and natural number; M, i and j are natural number;
Calculate mean value and the brightness variance yields of M the pixel of the i in region,
Brightness average:
Brightness variance yields:
According to described brightness average
with described brightness variance yields S
m 2, symbolize the size of M region affected by force of eyeglass.But specifically how to characterize, relevant with the selection of two circuit polarizers.
Be set in M region of eyeglass, the first brightness average recording before eyeglass assembling or processing is
the first brightness variance yields is S
m1 2; The the second brightness average recording after assembling or processing is
the second brightness variance yields is S
m2 2.
If there is not light and dark striped in M region of eyeglass, with the first brightness average
with the second brightness average
the size of M region institute affected by force of eyeglass as a comparison; If there is light and dark striped in M region of eyeglass, with the first brightness variance yields S
m1 2with the second brightness variance yields S
m2 2the size size of M region institute affected by force of eyeglass as a comparison.Particularly, be divided into again following two kinds of situations.
The first situation: the first circuit polarizer 102 is that Left-hand circular polarization device, the second circuit polarizer 103 are right-hand circular polarization device, or the first circuit polarizer 102 is that right-hand circular polarization device, the second circuit polarizer 103 are Left-hand circular polarization device.(1), while there is not light and dark striped in M region of eyeglass, using the size of brightness average as the size of judging this region affected by force of eyeglass.If
show that M region of eyeglass affected by force after assembling or processing becomes large; If
m the region that shows eyeglass is subject to the impact of stress constant after assembling or processing; If
show that M region of eyeglass affected by force after assembling or processing diminishes.(2) if there is light and dark striped in M region of eyeglass, think that the impact size of the suffered stress of eyeglass in this region is mainly evaluated by the large size of brightness variance in this region, that is to say with S
m1 2and S
m2 2size as the foundation of M region institute affected by force size of judgement eyeglass, and ignore
with
impact.Particularly, if S
m2 2>S
m1 2, show M region assembling of eyeglass or process rear affected by force to become large; If S
m2 2=S
m1 2, show that M region affected by force after assembling or processing of eyeglass is constant; If S
m2 2<S
m1 2, show that M region affected by force after assembling or processing of eyeglass diminishes.By the first brightness average
with the second brightness average
relatively or the first brightness variance yields S
m1 2with the second brightness variance yields S
m2 2comparison, can judge easily M selected region of eyeglass in the size of processing or assembling front and back institute affected by force.The method is simple, quick, thereby provides important reference for eyeglass stress detects.
The second situation: the first circuit polarizer 102 and the second circuit polarizer 103 are Left-hand circular polarization device or are right-hand circular polarization device.(1), while there is not light and dark striped in M region of eyeglass, using the size of brightness average as the size of judging this region affected by force of eyeglass.Particularly,
show that M region of eyeglass affected by force after assembling or processing diminishes; If
m the region that shows eyeglass is subject to the impact of stress constant before and after assembling or processing; If
show to be subject to the impact of stress to become large after M region assembling of eyeglass or processing.(2) if there is light and dark striped in M region of eyeglass, think that the impact size of the suffered stress of eyeglass in this region is mainly evaluated by the brightness variance size in this region, that is to say should be with S
m1 2and S
m2 2size as basis for estimation, ignore
with
impact.Particularly, if S
m2 2>S
m1 2, show M region assembling of eyeglass or process rear affected by force to increase; If S
m2 2=S
m1 2, show that M region affected by force after assembling or processing of eyeglass is constant; If S
m2 2<S
m1 2, represent that M region affected by force of assembling or the rear eyeglass of processing reduces.By the first brightness average
with the second brightness average
contrast or the first brightness variance yields S
m1 2with the second brightness variance yields S
m2 2comparison, can judge easily M selected region of eyeglass in the size of processing or assembling front and back institute affected by force.The method is simple, quick, thereby provides important reference for eyeglass stress detects.
Comparison for affected by force size between eyeglass zones of different, when the selection of two circular polarization devices is constant, namely the first circuit polarizer 102 is Left-hand circular polarization device, the second circuit polarizer 103 is that right-hand circular polarization device or the first circuit polarizer 102 are right-hand circular polarization device, when the second circuit polarizer 103 is Left-hand circular polarization device or is right-hand circular polarization device for Left-hand circular polarization device or the first circuit polarizer 102 and the second circuit polarizer 103, comparative approach and conclusion with and the same selection area of eyeglass (for example above-mentioned in M selected region) assembling or to process the situation of front and back identical.
In addition, for formula
, also can change the poor S of luminance standard into
mrepresent, its decision method is with using brightness variance yields S
mdecision method the same, S now
mvalue be S
m 2extraction of square root value.
Now how concrete example calculates in N the region of delimiting in eyeglass and obtains the M(M≤N) brightness average and the variance yields in individual region.In M the region of supposing to choose, have i pixel value, j pixel value in this i pixel value is X
mj.
If M gets 1, X
11first pixel value that represents first region, X
12represent second pixel value in first region, X
1jj the pixel value that represents first region,
the mean value that represents i pixel value in first region.
According to formula, obtain brightness average and the brightness variance yields of i pixel value in the 1st region:
Brightness average:
Brightness variance yields:
Try to achieve the brightness average in first region
with brightness variance yields S
1 2, and according to the size of these two values, characterize eyeglass in the size of this region institute affected by force.It should be noted that, this method can not be measured the real stress intensity of eyeglass selection area, can only characterize eyeglass in the size of this region institute affected by force.These two values provide important foundation for eyeglass stress detects.
In above-mentioned formula, N=4K+1, M, i, j is natural number, j≤i, K is 0 and natural number;
The size of the stress that can obtain other regions that mark off in eyeglass stress envelope uses the same method.
Due to N=4K+1, for the size of N value, can be according to actual needs rational value.For example K gets 0, and N equals 1, and stress envelope is exactly 1 differentiation Butut; K gets 2, and N equals 9, and stress envelope is exactly 9 differentiation Bututs; Get K and get 3, N equals 13, and stress envelope is exactly 13 differentiation Bututs.According to people by eye custom, conventionally N value is got to 9, i.e. common 9 district figure in spectacles industry.This 9th district figure be take center of lens as the center of circle, marks from inside to outside three concentric circless respectively with the first diameter, Second bobbin diameter and the 3rd diameter.These three concentric circless form the first border circular areas, the second border circular areas and the 3rd border circular areas.Again respectively becoming with surface level ± two straight lines of 45 ° are divided into separately 4 parts by the second border circular areas and the 3rd border circular areas, but the first border circular areas are not divided.For the division in these 9 regions, difference nine regions, called after first area to the, 9 regions.But the particular location for the name in these 9 regions in 3 concentric circless, is very flexibly, is not specifically limited.
Concrete, with reference to figure 3, Fig. 3 is 9 Division schematic diagram of eyeglass stress envelope.Take the first border circular areas as first area, and first area is for characterizing the region of the eyeglass using when human eye is faced the place ahead, and this region is the most frequently used region of eyeglass, is also most important region; The part region that belongs to respectively the second border circular areas and the 3rd border circular areas on right side, first area is the 3rd region and SECTOR-SEVEN territory, the lens area that the 3rd region and SECTOR-SEVEN territory are used for characterizing the right apparent time of human eye; The part region that belongs to respectively the second border circular areas and the 3rd border circular areas in left side, first area is the 5th region and the 9th region, the lens area that the 5th region and the 9th region are used for characterizing the left apparent time of human eye; The part region that belongs to respectively the second border circular areas and the 3rd border circular areas of first area upside is second area and the 6th region, the lens area of using when look up for human eye in these two regions; The part region that belongs to respectively the second border circular areas and the 3rd border circular areas of first area downside is the 4th region and Section Eight territory, the lens area of using when these two regions are overlooked for human eye.For the 4th region and Section Eight territory, also can be suitable for the stress test of progressive additional lens.Eyeglass stress envelope is implemented to the division in 9th district, and measure the value of the sign stress intensity in each region, can reflect intuitively the stress distribution situation of eyeglass, make people according to each regional stress distribution situation, judge the quality of lens quality, be particularly conducive to region that people judge that eyeglass is often used such as the quality of lens quality in first area.
Particularly, foregoing in eyeglass stress envelope, take center of lens as the center of circle, with the first diameter, Second bobbin diameter and the 3rd diameter, mark from inside to outside three concentric circless, its diameter is followed successively by φ 6mm, φ 12mm and φ 18mm.Choosing of these three groups of diameter values is to calculate apart from the distance of eyeglass according to the structure of human eye and human eye.In addition, center and the center of lens of eyeglass stress envelope are arranged on optical axis, so the center of eyeglass stress envelope is also just equivalent to center of lens.
With reference to figure 4, for myopia or farsightedness, during wearing spectacles, pupil size is about 3-5mm, and the distance D 1 of eyeglass 203 elongation films 202 is about 12mm, and the distance D 3 on the summit of human eye node O elongation film 202 is about 7mm, and the long D4 of human eye axis oculi is about 24mm.By anatomy of human eye Xue Zhi, the most responsive region of human eye sensitization is called macular area in addition, sees that the diameter of 201. macular areas 201 in Fig. 3 is about 5.5mm.As shown in Figure 3, the positive apparent time of human eye, the use region of the corresponding eyeglass 203 of macular area 201 is about lens center and is about the border circular areas of Φ 6mm around, thereby the first diameter of dividing is 6mm.
When human eye is used, 201 pairs of light of macular area are the most responsive, also can sensitization but macular area 201 is outer, but photoperceptivity is weaker than macular area 201, and the outer human eye of macular area also can be used, thereby expands eyes imaging scope.After putting on one's glasses in addition, human eye can rotate, cause human eye can use near the diameter 6mm of center of lens region in addition, thereby while detecting eyeglass critical area stress, can not only limit near the 6mm diameter region of center of lens, therefore eye-observation expanded range is arrived to two circles of outside, the second border circular areas and the 3rd border circular areas, be used as the amplification to the first border circular areas.Therefore Second bobbin diameter is taken as Φ 12, the 3rd diameter is Φ 18mm, with this, expands the stress measurement scope in the lens region that human eye mainly uses.
In addition, in the time of need being affixed on the lens of anterior corneal surface for test Ortho-K or contact lenses etc., the diameter of the first border circular areas, the second border circular areas and the 3rd border circular areas of corresponding stress envelope is adjusted into successively: Φ 2.5mm, Φ 5mm, Φ 7.5mm. i.e. the first diameter are Φ 2.5mm, Second bobbin diameter is Φ 5mm, and the 3rd diameter is Φ 7.5mm.
In the present invention, area source 101 can uniform area light source, can be also non-homogeneous area source, but in order to obtain better eyeglass stress test effect, be preferably uniform area light source.
The foregoing is only preferred embodiment of the present invention, not in order to limit the present invention, all any modifications of doing within the spirit and principles in the present invention, be equal to and replace and improvement etc., within all should being included in protection scope of the present invention.