CN112393883A - Uniform integrating sphere device and measuring method thereof - Google Patents

Abstract

The invention discloses a uniform integrating sphere device and a measuring method thereof, wherein the device comprises a first hemisphere and a second hemisphere, the first hemisphere and the second hemisphere are both hollow cavities, the first hemisphere is provided with a light inlet, the joint part of the first hemisphere and the second hemisphere is provided with a plurality of light outlets, each light outlet is connected with a first receiver, each first receiver is converged at the second receiver through an optical fiber, incident light enters each hemisphere through the light inlet and is uniformly reflected, then the incident light is emitted from each light outlet, and the incident light is converged at the second receiver through each first receiver. Based on the plurality of light-emitting holes, incident light is incident from the light-emitting holes, is emitted from the light-emitting holes after being uniformly reflected for multiple times in the uniform integrating sphere, and is converged to the second receiver through the first receivers, so that the stable output of the total luminous flux is realized, and the error between the luminous flux of the light-emitting holes and the luminous flux of the light-emitting holes is reduced.

Description

Uniform integrating sphere device and measuring method thereof

Technical Field

The invention relates to the technical field of spectral measurement, in particular to a uniform integrating sphere device and a measuring method thereof.

Background

The integrating sphere is a spherical cavity, and is generally formed by joining two hemispherical cavities (a left hemisphere 5 and a right hemisphere 6), the surface of the cavity is coated with a broad-spectrum high-reflectivity diffusion coating, and a light inlet 1 and a light outlet 2 are formed on the surface of the cavity, and a receiver 3 such as an optical fiber head or a photosensitive element is generally arranged at the light outlet. The central axis of the light outlet hole is vertical to the central axis of the light inlet hole or forms an angle of 45 degrees. The integrating sphere may have other shapes such as a sphere or a square. The integrating sphere has the function of enabling incident light 4 incident from the light inlet 1 to be reflected for multiple times in the integrating sphere and forming uniform illumination on the wall of the spherical cavity; the change of the luminous flux of the light outlet hole, which is influenced by the change of the direction of the incident light, is eliminated, so that the luminous flux value received by the receiver 3 is only in direct proportion to the incident luminous flux value of the light inlet hole, as shown in fig. 1.

The existing integrating sphere is only provided with a light outlet 2, the reflectivity of a high-reflectivity diffusion coating on the surface of a cavity cannot reach 100%, and the coating is not completely ideal in diffuse reflection, so that the direction of incident light 4 is different, and the non-uniformity of the illuminance of each point on the surface of the cavity can be influenced; i.e. the light flux values measured by the exit pupil receiver vary slightly with the direction of the incident light. As shown in fig. 2, the same luminous flux varies depending on the incident direction, and the measured value at the light exit hole will vary in both cases a and B.

The spectral transmittance (transmittance) measurement is a relative measurement, which is the ratio of the intensity of the light signal received by the receiver before and after the measurement sample 7 is placed. The integrating sphere should function as much as possible to influence the measurement result by other factors (such as the incident direction of light) besides the luminous flux.

When the spectrum of the plate glass is measured and transmitted by the existing integrating sphere, the incident direction of light rays cannot be changed by the plate glass, so that the generated measurement error is small. However, when the spectral transmittance characteristics of the lens or lens are measured, the incident direction of the light is changed by the lens or lens (as shown in fig. 3), so that the direction of the light before and after the sample 7 is put into the measurement sample is not consistent, which affects the accuracy of the measurement, and the direction of the light is changed each time the sample 7 is put into the measurement sample, which also affects the precision of the measurement due to the deviation between the center of the sample and the center of the light inlet. Especially for lenses or lenses with a shorter focal length, the measurement error is larger. The spectral transmittance characteristics of the lens or the lens are difficult to accurately measure by the existing spectrometer. Often replaced by measuring the test strip or its reflectance spectral characteristics.

Disclosure of Invention

In order to solve one of the above technical problems, an object of the present invention is to provide a uniform integrating sphere device with small spectral measurement error and good repeatability and a method thereof.

The first technical scheme adopted by the invention is as follows:

the utility model provides an even integrating sphere device, includes first hemisphere and second hemisphere, first hemisphere with the second hemisphere is the cavity body, first hemisphere is equipped with into the unthreaded hole, the first hemisphere with the junction of second hemisphere is equipped with a plurality of light-emitting hole, each light-emitting hole all is connected with first receiver, each first receiver passes through optic fibre and merges in the second receiver, and the incident light passes through into each after the even reflection in the hemisphere is gone into through into the unthreaded hole, from each light-emitting hole outgoing to through each first receiver converge in the second receiver.

Optionally, the number of the light emitting holes is at least two, and the number of the light emitting holes is the same as that of the first receivers.

Optionally, the light emitting holes are distributed at equal intervals on the joint of the first hemisphere and the second hemisphere.

Optionally, the light inlet hole is positioned at the geometric center of the first hemisphere.

Optionally, a central axis of each light exit hole is perpendicular to a central axis of the light entrance hole.

Optionally, the central axis of each light outlet hole and the central axis of the light inlet hole may also form an angle of 45 °.

Optionally, the first receiver is embedded in the light exit hole.

Optionally, the inner surface of the cavity of each hemisphere is coated with a reflective layer.

Optionally, the wavelength of light corresponding to the reflective layer is 400nm to 700 nm.

The second technical scheme adopted by the invention is as follows:

a measuring method of a uniform integrating sphere comprises a first hemisphere and a second hemisphere, wherein each hemisphere is a cavity, the first hemisphere is provided with a light inlet, a plurality of light outlets are formed in the joint of the first hemisphere and the second hemisphere, each light outlet is connected with a first receiver, and each first receiver is converged in a second receiver through an optical fiber, and the measuring method comprises the following steps:

the incident light enters each hemisphere through the light inlet hole to be uniformly reflected;

the uniformly reflected incident light is emitted from each light outlet hole and is combined with the second receiver through each first receiver.

The invention has the beneficial effects that: based on a plurality of light-emitting holes that set up, when the direction of incident light changed, the luminous flux of some light-emitting holes reduced, and the luminous flux of another part light-emitting hole correspondingly increased, closed the luminous flux of each light-emitting hole in the second receiver through the first receiver that is connected with each light-emitting hole, realized the stability of total luminous flux, avoided single light-emitting hole moreover because incident light reflection uneven with the few luminous flux loss that leads to of light-emitting hole, reduced the error of entering light hole luminous flux and light-emitting hole luminous flux.

Drawings

FIG. 1 is a cross-sectional view of a single light-extraction aperture integrating sphere of the prior art;

FIG. 2 is a cross-sectional view of an integrating sphere A and an integrating sphere B with a single light exit aperture in the prior art under two incident conditions;

FIG. 3 is a cross-sectional view of an integrating sphere with a single exit pupil of the prior art before and after placement of a measurement sample;

FIG. 4 is a schematic structural diagram of a uniform integrating sphere device provided by the present invention;

FIG. 5 is a schematic diagram of a uniform integrating sphere with 4 light-exiting apertures according to an embodiment of the present invention;

FIG. 6 is a schematic diagram of a repeatability error of a single light-exit aperture integrating sphere measurement lens;

FIG. 7 is a schematic diagram of a repeatability error of a uniform integrating sphere measurement lens with 4 light-emitting holes according to an embodiment of the present invention;

FIG. 8 is a diagram of a uniform integrating sphere with 4 light-emitting holes according to an embodiment of the present invention;

fig. 9 is a schematic step diagram of a measuring method of a uniform integrating sphere device according to a second embodiment of the present invention.

Detailed Description

Example one

As shown in fig. 4, an even integrating sphere device includes a first hemisphere and a second hemisphere, each hemisphere is a cavity, the first hemisphere is provided with a light inlet, a plurality of light outlets are provided at a joint portion of the first hemisphere and the second hemisphere, each light outlet is connected with a first receiver, each first receiver is converged in the second receiver through an optical fiber, incident light enters each hemisphere through the light inlet and is emitted from each light outlet after being reflected evenly, and the incident light is converged in the second receiver through each first receiver.

In this embodiment, the first hemisphere and the second hemisphere are hemispheres having the same size, and the first receiver and the second receiver include, but are not limited to, an optical fiber connector, a photosensitive element, and the like. The working principle of the device is as follows: the incident light is incident from the light inlet hole positioned on the first hemisphere, and the luminous flux of the incident light incident from the light inlet hole is recorded, after the incident light is uniformly reflected for multiple times in the uniform integrating sphere, the incident light is emitted from the light outlet holes positioned on the joint part of the first hemisphere and the second hemisphere, and the incident light is converged in the second receiver through the first receivers, so that the luminous flux loss caused by the fact that the incident light is reflected unevenly and the light outlet holes are few in a single light outlet hole is avoided, the stable output of the total luminous flux is realized, and the error between the luminous flux of the light inlet hole and the luminous flux of the light outlet hole is reduced.

Optionally, the number of the light emitting holes is at least two, and each light emitting hole is the same as the number of the first receivers.

In this embodiment, the light emitting holes and the first receivers are arranged in a one-to-one correspondence, which is helpful for incident light uniformly reflected in the cavity to be emitted from the light emitting holes and enter the first receivers, so that the light flux of the light emitting holes can be conveniently recorded.

Optionally, the light emitting holes are distributed at equal intervals on the joint of the first hemisphere and the second hemisphere.

In this embodiment, the light emitting holes are distributed at equal intervals at the joint of the first hemisphere and the second hemisphere, so that incident light entering the light inlet is uniformly reflected and then uniformly emitted from the light emitting holes.

Optionally, the light inlet hole is placed at the geometric center of the first hemisphere.

In this embodiment, the light inlet hole is disposed at the geometric center of the first hemisphere, so that the light flux loss caused by the position deviation of the light inlet hole can be avoided, and the precision of the measurement result is prevented from being affected.

Optionally, the central axis of each light exit hole is perpendicular to the central axis of the light entrance hole.

Optionally, the central axis of each light exit hole and the central axis of the light entrance hole may also form an angle of 45 °.

Optionally, the first receiver is embedded in the light exit hole.

Optionally, the inner surface of the cavity of each hemisphere is coated with a reflective layer.

Optionally, the light wavelength corresponding to the reflective layer is 400nm to 700 nm.

Example two

As shown in fig. 9, a method for measuring a uniform integrating sphere device, wherein the uniform integrating sphere device includes a first hemisphere and a second hemisphere, each hemisphere is a hollow cavity, the first hemisphere has a light inlet, a plurality of light outlets are disposed at a joint of the first hemisphere and the second hemisphere, each light outlet is connected to a first receiver, and each receiver is returned to the second receiver through an optical fiber, the method for measuring a uniform integrating sphere includes the following steps:

s1, the incident light enters each hemisphere through the light inlet hole to be reflected uniformly;

and S2, the uniformly reflected incident light is emitted from each light outlet and is combined with the second receiver through each first receiver.

DETAILED DESCRIPTION OF EMBODIMENT (S) OF INVENTION

Referring to fig. 5 to 8, the present embodiment discloses a uniform integrating sphere with four light emitting holes, comprising a first hemisphere 5 and a second hemisphere 6, each hemisphere being a cavity, and the inner wall of the cavity is coated with a reflecting layer 8 with the corresponding optical wavelength of 400nm to 700nm, the geometric center of the first hemisphere 5 is provided with a light inlet hole 1, the joint part of the first hemisphere 5 and the second hemisphere 6 is provided with four light outlet holes (as shown in figure 5, a light outlet hole 21, a light outlet hole 22, a light outlet hole 23 and a light outlet hole 24 are respectively arranged at equal intervals), the central axis of the light inlet 1 is perpendicular to the central axes of the four light outlets, a branch optical fiber connector (an optical fiber connector 91, an optical fiber connector 92, an optical fiber connector 93, and an optical fiber connector 94, respectively, as shown in fig. 5) for connecting optical fibers is disposed in each light outlet, the optical fiber connectors are used for detecting the luminous flux of the light outlet, and the optical fiber connectors of the light outlets converge the light emitted from the light outlets to a common optical fiber connector 95.

The working principle of the integrating sphere device is as follows: incident light is incident from a light inlet hole 1 positioned at the geometric center of the first hemisphere 5, and the luminous flux of the incident light incident from the light inlet hole 1 is recorded, after the incident light is uniformly reflected by a reflecting layer 8 coated on the inner wall of each hemisphere cavity, the incident light is emitted from four light outlets (a light outlet hole 21, a light outlet hole 22, a light outlet hole 23 and a light outlet hole 24) arranged at the joint part of the first hemisphere 5 and the second hemisphere 6 at equal intervals, and light is converged into a common optical fiber joint 95 through each branch optical fiber joint (an optical fiber joint 91, an optical fiber joint 92, an optical fiber joint 93 and an optical fiber joint 94), so that the luminous flux loss caused by uneven reflection of the incident light and uneven distribution of the light outlets of a single light outlet hole is avoided, the stable output of the total luminous flux is realized, and the error between the luminous flux of the light inlet hole and the luminous flux of the light outlet hole is reduced.

Specifically, as shown in fig. 8, the uniform integrating sphere with four light exit holes in the present embodiment is a test performed on a japanese tsukamur electronic MCPD-3000 spectrometer, and compared with the prior art, the integrating sphere device with a single light exit hole separately tests the uniform integrating sphere with four light exit holes and the integrating sphere device with a single light exit hole, as shown in fig. 6 and 7, a repeatability error of the integrating sphere device with a single light exit hole is significantly larger than that of the uniform integrating sphere device with four light exit holes in the present embodiment, and a repeatability error of a general single light exit hole integrating sphere in data reality is more than six times larger than that of the integrating sphere with four light exit holes in the present embodiment.

While the preferred embodiments of the present invention have been illustrated and described, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (10)

1. The uniform integrating sphere device is characterized by comprising a first hemisphere and a second hemisphere, wherein the first hemisphere and the second hemisphere are both hollow cavities, the first hemisphere is provided with a light inlet, a plurality of light outlets are formed in the joint portion of the first hemisphere and the second hemisphere, each light outlet is connected with a first receiver, each first receiver is combined with a second receiver through an optical fiber, and incident light enters the hemispheres through the light inlets and is uniformly reflected, then exits from the light outlets, and is combined with the second receiver through the first receivers.

2. The device of claim 1, wherein there are at least two light-emitting holes, and each light-emitting hole is equal in number to each first receiver.

3. The device as claimed in claim 2, wherein the light emitting holes are equally spaced at the junction of the first hemisphere and the second hemisphere.

4. A uniform integrating sphere device in accordance with claim 1, wherein said light entrance hole is placed at the geometric center of said first hemisphere.

5. The device of claim 1, wherein the central axis of each of the light-emitting holes is perpendicular to the central axis of the light-entering hole.

6. The device of claim 5, wherein the central axis of each of the light exit holes may also be at an angle of 45 ° to the central axis of the light entrance hole.

7. A homogeneous integrating sphere apparatus according to claim 1, wherein said first receiver is disposed within said exit pupil.

8. A uniform integrating sphere device in accordance with claim 1, wherein the inner surface of each hemisphere cavity is coated with a reflective layer.

9. The device of claim 5, wherein the reflective layer has a wavelength of 400nm to 700 nm.

10. The measuring method of the uniform integrating sphere device is characterized in that the uniform integrating sphere device comprises a first hemisphere and a second hemisphere, each hemisphere is a cavity body, the first hemisphere is provided with a light inlet, a plurality of light outlets are formed in the joint portion of the first hemisphere and the second hemisphere, each light outlet is connected with a first receiver, and each first receiver is converged in the second receiver through an optical fiber, and the measuring method comprises the following steps:

the incident light enters each hemisphere through the light inlet hole to be uniformly reflected;

the uniformly reflected incident light is emitted from each light outlet hole and is combined with the second receiver through each first receiver.

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