CN104296683B - A kind of method measuring free-curved-surface-type - Google Patents

Abstract

A device and method for measuring the shape of a free-form surface belong to the field of optical microscopic imaging; the device includes: a sample to be tested, an electroluminescent film coated on the surface of the sample, positive and negative microelectrodes, an objective lens, an optical filter, a tube lens, CCD, electroluminescent film lighting part, optical imaging measurement part, this method coats the electroluminescent fluorescent dielectric film on the sample surface, and the sample surface is lit up after power-on, combined with the optical detection light path, the measurement of the free-form surface can be realized. The odd and even stripes on the surface of the sample are respectively illuminated by electroluminescence to replace the traditional optical illumination, which avoids the problem of unmeasurable large curvature parts caused by the illumination aperture, and can measure the surface morphology of samples with a large angle between the normal line and the axial direction. .

Description

A Method for Measuring the Shape of Freeform Surface

technical field

A device and method for measuring the surface shape of a free-form surface belong to the field of optical microscopic imaging.

Background technique

In the field of surface topography measurement and microscopic imaging, the measurement of optical free-form surfaces has always been a very challenging problem. Common optical measuring instruments, such as confocal microscopes, illuminate the surface of the sample by projecting light onto the sample through structures such as lenses. However, the traditional optical illumination mode cannot fully illuminate the area where the sample surface normal and the optical axis have an inclination angle of more than 45 degrees and effectively collect the sample surface signal light.

Contents of the invention

In order to solve the above problems, the present invention discloses a device and method for measuring the surface profile of a free-form surface, which solves the problem of high-precision measurement of the surface topography of a free-form surface sample.

The purpose of the present invention is achieved like this:

A device and method for measuring the shape of a free-form surface, comprising:

A device for measuring the profile of a free-form surface, comprising:

Electroluminescent film lighting part and optical imaging measurement part;

The electroluminescent film lighting part is composed of the sample to be tested, an electroluminescent film plated on the surface of the sample and a microelectrode;

The optical imaging measurement part includes an objective lens, an optical filter, a tube lens and a CCD sequentially along the propagation direction of the collected light signal.

In the above-mentioned device for measuring free-form surface type, the electroluminescent film is composed of a cathode layer, a light-emitting layer and a transparent anode layer with uniform thickness, the total thickness is not more than 4 μm, and the thickness of the light-emitting layer is not more than 1 μm. The light-emitting layer is The organic layer is composed of an electron transport layer, a monochromatic organic light-emitting layer and a hole injection layer. The electroluminescent film is composed of parallel electroluminescent strips, and there are uncoated, In a tiny blank area with a width less than 5nm, there are micro-electrodes at both ends of each electroluminescent strip, the cathode layer is connected to the negative pole of the micro-electrode, and the transparent anode layer is connected to the positive pole of the micro-electrode.

The method for measuring the surface profile of a free-form surface implemented on the above-mentioned device for measuring the surface profile of a free-form surface comprises the following steps:

The first step is to generate an electroluminescent film on the surface of the sample to be tested. The electroluminescent film is composed of a cathode layer, a light-emitting layer and a transparent anode layer with uniform thickness, the total thickness is not more than 4 μm, and the thickness of the light-emitting layer is not more than 1 μm. The luminescent layer is an organic layer, which is composed of an electron transport layer, a monochromatic organic luminescent layer and a hole injection layer. The electroluminescent film is composed of parallel electroluminescent strips, and between two adjacent electroluminescent strips There is a small blank area with or without coating, and the width is less than 5nm. There are micro-electrodes at both ends of each electroluminescent strip. The cathode layer is connected to the negative electrode of the micro-electrode, and the transparent anode layer is connected to the positive electrode of the micro-electrode;

The second step is to adjust the distance between the objective lens and the sample to be tested, so that the image plane of a certain layer structure on the surface of the sample to be tested coincides with the image plane of the CCD photosensitive element, set the total movement distance a of the objective lens, and the step distance b of the objective lens, and set the variable i equal to 0;

The third step is to move the objective lens along the axial direction for a distance b;

The fourth step, from left to right, energizes the microelectrodes of the electroluminescent strips located in odd positions to make the corresponding electroluminescent strips emit light, and complete the luminescent work of a part of the electroluminescent film on the surface of the sample to be tested, and take pictures of this layer The image of the sample, obtaining the two-dimensional data D _xym of the odd-numbered area of the layer structure;

Step 5: From left to right, energize the microelectrodes of the electroluminescent strips located in even positions to make the corresponding electroluminescent strips emit light, and complete the luminescent work of the electroluminescent film on the surface of the sample to be tested. The image of the layer sample, to obtain the two-dimensional data D _xyn of the even region of the layer structure;

The sixth step is to combine D _xym and D _{xyn into two-dimensional data D xyi according} to the odd-numbered area and the even-numbered area, and add 1 to the variable i;

The seventh step is to judge whether i×b is greater than or equal to a, if so, enter the eighth step, otherwise repeat the third step to the sixth step;

The eighth step is to form a three-dimensional matrix from the two-dimensional data D _xyi obtained by measuring all the axial positions, extract a one-dimensional array along z for each pixel point xy, find the maximum point in the array, and record the value corresponding to the maximum value axial position;

In the ninth step, the axial positions recorded by all the xy pixels are combined with the positions corresponding to the xy pixels to reconstruct the surface profile of the sample.

The above-mentioned method for measuring the surface profile of a free-form surface further includes a tenth step of cleaning off the electroluminescent film and the microelectrode on the surface of the sample to be tested.

Beneficial effect:

Compared with the existing microscopic measurement technology, the present invention first coats the electroluminescent film on the surface of the sample with a fluorescent lighting film to make it emit light by stimulated radiation, and then on this basis, discloses a method for measuring free-form surface Method, this technical improvement, through electroluminescence, the present invention overcomes the problem that the surface of the free-form surface with a slope greater than 45 degrees cannot be uniformly and fully illuminated and the signal light is collected in the illumination mode of the common measurement method, thereby measuring The sample surface topography includes the area where the angle between the normal line and the axial direction is greater than 45°. In addition, by illuminating the odd-numbered and even-numbered strips separately, the interference of imaging signals in adjacent areas is separated, and the measurement resolution is improved compared with the method of illuminating the entire sample at the same time.

Description of drawings

Fig. 1 is a structural schematic diagram of a device for measuring the profile of a free-form surface according to the present invention.

Figure 2 is a schematic diagram of an electroluminescent thin film.

In the figure: 1 sample to be tested, 2 electroluminescent film coated on the surface of the sample, 3 positive and negative microelectrodes, 4 objective lens, 5 filter, 6 tube mirror, 7CCD, 8 electroluminescent film lighting part, 9 optical imaging measuring part.

detailed description

The specific embodiments of the present invention will be further described in detail below in conjunction with the accompanying drawings.

Specific embodiment one

This embodiment is a device embodiment.

A schematic diagram of a device for measuring the shape of a free-form surface in this embodiment is shown in FIG. 1 . The unit includes:

Electroluminescent film lighting part 8 and optical imaging measurement part 9;

The electroluminescent film lighting part is composed of a sample to be tested 1, an electroluminescent film 2 plated on the surface of the sample 1, and positive and negative microelectrodes 3;

The optical imaging part includes objective lens 4, optical filter 5, tube lens 6 and CCD7 in sequence along the propagation direction of the collected optical signal.

In the above-mentioned device for measuring free-form surface profile, the electroluminescent film as shown in Figure 2 has a thickness of no more than 4 μm and is composed of a cathode layer, a luminescent layer and a transparent anode layer, and each layer has a uniform thickness; The film thickness of the light-emitting layer is not more than 1 μm, and the light-emitting layer is an organic layer, which is composed of an electron transport layer, a monochromatic organic light-emitting layer and a hole injection layer. The electroluminescent film is made in different regions and arranged in strips in sample 1 On the surface, there are tiny blank areas without coating between different strips, and the width of the blank area is less than 5nm. There are positive and negative microelectrodes at both ends of each area. The cathode layer is connected to the negative microelectrode, and the transparent anode layer is connected to the positive microelectrode. Among them, the thickness of the light-emitting layer does not exceed 1 μm, which can improve the measurement accuracy. When the film thickness is greater than 4 μm, interference signals will be introduced; the uniform thickness of each layer can avoid breakdown of the film when electrified; there are small gaps between different strips There is no coating in the area, and the width of the blank area is less than 5nm. The blank area can prevent two adjacent areas from being lit at the same time when the film is energized, thereby reducing the resolution of the system. When the width of the blank area is greater than 5nm, the measurement blind area is large, and the measurement resolution cannot be guaranteed.

Specific embodiment two

This embodiment is an embodiment of the method implemented on the device described in the first specific embodiment.

A kind of method for measuring free-form surface profile of the present embodiment, comprises the following steps:

In the first step, a cathode layer, a light-emitting layer, a transparent anode layer and a microelectrode with a total thickness of no more than 4 μm are formed on the surface of the sample 1, and the thickness of each layer is uniform; the film thickness of the light-emitting layer is no more than 1 μm, and the light-emitting layer is an organic layer. It is composed of an electron transport layer, a monochromatic organic light-emitting layer and a hole injection layer. The electroluminescent film is made in different regions and arranged in strips on the surface of sample 1. There are small blank areas without coating between different strips, and the blank areas are The width is less than 5nm, and there are positive and negative microelectrodes at both ends of each region, the cathode layer is connected to the negative microelectrode, and the transparent anode layer is connected to the positive microelectrode;

The second step is to adjust the distance between the objective lens 4 of the optical imaging measurement part and the sample 1, so that the image plane of a certain layer structure on the surface of the sample 1 coincides with the image plane of the CCD photosensitive element, and the total movement stroke a of the objective lens 4 is set, and the objective lens 4 steps Enter the distance b, let the variable i equal to 0;

The third step is to move the objective lens 4 along the axial direction for a distance b;

The fourth step is to set the number of the odd-numbered block area on the surface of sample 1 from left to right to be odd, and the number of the even-numbered block area to be even; to pass a direct current between the positive microelectrode and the negative microelectrode of all odd-numbered areas, so that the electric current The luminescent film emits light, completes the work of electroluminescence lighting a part of the luminescent film on the surface of sample 1, takes an image of this layer of sample 1, and obtains the two-dimensional data D _xym of the odd numbered area of the layer structure; the above-mentioned odd and even partition lighting method can improve the measurement device resolution;

The fifth step is to pass direct current between the positive microelectrode and the negative microelectrode in all even-numbered areas to make the electroluminescent film emit light, complete the work of electroluminescent lighting another part of the luminescent film on the surface of sample 1, and take pictures of this layer of samples 1, obtain the even-numbered two-dimensional data D _xyn of the layer structure;

The sixth step is to combine D _xy0 D _xy1 into two-dimensional data D _xyi according to the odd-numbered area and the even-numbered area, and add 1 to the variable i;

The seventh step is to judge whether i×b is greater than or equal to a, if so, enter the eighth step, otherwise repeat the third step to the sixth step;

The eighth step is to form a three-dimensional matrix from the two-dimensional data D _xyi obtained by measuring all the axial positions, extract a one-dimensional array along z for each pixel point xy, find the maximum point in the array, and record the value corresponding to the maximum value axial position;

In the ninth step, the axial positions recorded by all xy pixels are combined with the positions corresponding to the xy pixels to reconstruct the surface profile of sample 1.

Specific embodiment three

This embodiment is a method embodiment.

In this embodiment, on the basis of the specific embodiment 2, an eleventh step is added to clean all the films on the surface of the sample 1 and the microelectrodes near the surface of the sample 1. In this step, the recovery of the surface topography of the sample can be realized.

The present invention is not limited to the above-mentioned best implementation mode, and anyone should know that structural changes or method improvements made under the inspiration of the present invention, all technical solutions that are identical or similar to the present invention, all fall within the scope of protection of the present invention within.

Claims (2)

1. the method measuring free-curved-surface-type,

The device measuring free-curved-surface-type used, including:

Electroluminescent membrane illumination part (8) and Optical imaging measurement part (9)；

Described electroluminescent membrane illumination part (8) is by testing sample (1), the electroluminescent film that is plated in sample (1) surface (2) form with microelectrode (3)；

Described Optical imaging measurement part (9) is followed successively by object lens (4), optical filter (5), pipe along collecting lightray propagation direction Mirror (6) and CCD (7)；

Described electroluminescent film is made up of cathode layer in uniform thickness, luminescent layer and transparent anode layer, and gross thickness is less than 4 μm, light emitting layer thickness is less than 1 μm, and described luminescent layer is organic matter layer, by electron transfer layer, monochromatic organic luminous layer Forming with hole injection layer, described electroluminescent membrane is made up of parallel electroluminescent bar, has between adjacent two electroluminescent bars Without plated film, width less than the small white space of 5nm, all there is a microelectrode (3) at each electroluminescent bar two ends, cathode layer with Microelectrode (3) negative pole is connected, and transparent anode layer is connected with microelectrode (3) positive pole；

It is characterized in that, comprise the following steps:

The first step, at testing sample (1) Surface Creation electroluminescent film (2), described electroluminescent film is uniform by thickness Cathode layer, luminescent layer and transparent anode layer composition, gross thickness be less than 4 μm, light emitting layer thickness be less than 1 μm, described Luminescent layer is organic matter layer, is made up of electron transfer layer, monochromatic organic luminous layer and hole injection layer, described electroluminescent membrane by Parallel electroluminescent bar composition, with or without plated film, small clear area that width is less than 5nm between adjacent two electroluminescent bars Territory, each electroluminescent bar two ends all have microelectrode (3), cathode layer to be connected with microelectrode (3) negative pole, and transparent anode layer is with micro- Electrode (3) positive pole is connected；

Second step, the distance between regulation object lens (4) and testing sample (1), make testing sample (1) surface Rotating fields Image planes overlap with CCD photo-sensitive cell image planes, arrange the total movement travel a of object lens (4), object lens (4) step distance b, and order becomes Amount i is equal to 0；

3rd step, makes object lens (4) distance b axially movable；

4th step, from left to right direction, give microelectrode (3) energising of the electroluminescent bar being positioned at odd positions, make the electricity of correspondence Photoluminescence bar is luminous, completes the luminous work of a part of electroluminescent membrane in testing sample (1) surface, shoots this layer of sample (1) Image, obtain the odd zone 2-D data D of this Rotating fields_xym；

5th step, from left to right direction, give microelectrode (3) energising of the electroluminescent bar being positioned at even number position, make the electricity of correspondence Photoluminescence bar is luminous, completes the luminous work of testing sample (1) surface another part electroluminescent membrane, shoots this layer of sample (1) Image, obtain the even number region 2-D data D of this Rotating fields_xyn；

6th step, by D_xymAnd D_xynIt is combined into 2-D data D according to odd zone and even number region_xyi, make variable i add 1；

7th step, it is judged that whether i × b is more than or equal to a, if yes then enter the 8th step, otherwise repeats the 3rd step to the 6th step；

All axial locations are measured the 2-D data D of gained by the 8th step_xyiComposition three-dimensional matrice, for each pixel xy edge Z extracts one-dimension array, finds maximum of points in this array, and records the axial location corresponding to this maximum；

The position grouping that 9th step, axial location that all xy pixels are recorded and xy pixel are corresponding, thus reconstruct sample (1) Face, surface type.

A kind of method measuring free-curved-surface-type the most according to claim 1, it is characterised in that also include the tenth step, Wash testing sample (1) surface electroluminescent film (2) and microelectrode (3).