JP-7855589-B2 - 3D ranging module and 3D ranging system

JP7855589B2JP 7855589 B2JP7855589 B2JP 7855589B2JP-7855589-B2

Inventors

中野慎吾
浅野拓也
林茂生

Assignees

ヌヴォトンテクノロジージャパン株式会社

Dates

Publication Date: 20260508
Application Date: 20220711
Priority Date: 20210729

Claims (20)

A light source that emits laser light, A lens module including a lens that focuses the light reflected by an object from the irradiated laser beam, an image sensor that receives the light focused by the lens, and a lens barrel that encloses the space between the lens and the image sensor and supports the lens, The lens module and the object are positioned and have a lens cover that is transparent to the wavelength of the laser light, In a cross-sectional view when the lens barrel is cut along a plane containing the optical axis of the lens, A three-dimensional distance measuring module wherein the first surface of the lens barrel facing the object includes a first inclined portion that is inclined to move away from the lens cover as it moves away from the optical axis.
The three-dimensional distance measuring module according to claim 1, wherein the first inclined portion is formed over the entire surface of the first surface.
The three-dimensional distance measuring module according to claim 1 or 2 , wherein the half-width of the light scattering angle of the laser light on the first surface is 45 degrees or more.
In the aforementioned cross-sectional view, The angle between the first inclined portion and the surface of the lens cover facing the lens module is 30 degrees or more, as described in claim 3, for the three-dimensional distance measuring module.
In the aforementioned cross-sectional view, The three-dimensional distance measuring module according to claim 1 or 2 , wherein the first inclined portion is linear.
When viewed from the direction of the optical axis, The outer shape of the lens barrel is similar in shape to the outer shape of the image sensor. The degree of inclination of the first inclined portion from a plane perpendicular to the optical axis is positively correlated with the distance between the optical axis and the outer end of the lens barrel, as described in claim 1 or 2 .
The three-dimensional distance measuring module according to claim 1 or 2, wherein the half-width of the light scattering angle of the laser light on the first surface is 7 degrees or less.
When viewing the lens from the object side of the lens cover, When ε is the maximum angle between the optical axis and the direction in which the front side of the lens can be seen, The three-dimensional distance measuring module according to claim 7, wherein the angle between the first inclined portion and the plane perpendicular to the optical axis is ε/2 or greater.
The lens cover has a member having an opening that encloses the lens when the lens is viewed from the lens cover in the direction of the optical axis of the lens, In the cross-sectional view obtained when the lens barrel is cut along a plane including the optical axis of the lens, Let B be the distance between the outer end of the lens and the outer end of the aperture. Let H1 be the distance between the lens cover and the center of the lens. Let H2 be the distance between the lens cover and the second surface of the member facing the lens cover. When the angle between the line connecting the center of the lens and the outer edge of the image sensor and the optical axis is θ, A three-dimensional distance measuring module according to claim 1 or 2, satisfying the relationship (H1 + H2)・tanθ ≤ B.
The three-dimensional distance measuring module according to claim 1 or 2 , wherein the third surface of the lens cover facing the lens module includes a third inclined portion that is inclined to move away from the lens module as it moves away from the optical axis.
A light source that emits laser light, A lens that focuses the light reflected by the object from the irradiated laser beam, An image sensor that receives light focused by the aforementioned lens, A lens cover, which is transparent to the wavelength of the laser light, is positioned between the lens and the object. The lens cover has a member having an opening that encloses the lens when the lens is viewed from the lens cover in the direction of the optical axis of the lens, In a cross-sectional view when the lens is cut along a plane including the optical axis, Let B be the distance between the outer end of the lens and the outer end of the aperture. Let H1 be the distance between the lens cover and the center of the lens. Let H2 be the distance between the lens cover and the second surface of the member facing the lens cover. When the angle between the line connecting the center of the lens and the outer edge of the image sensor and the optical axis is θ, A 3D distance measuring module that satisfies the relationship (H1 + H2) * tanθ ≤ B.
When viewed from the direction of the optical axis, The three-dimensional distance measuring module according to claim 11, wherein the outer shape of the opening is barrel-shaped.
In the aforementioned cross-sectional view, The three-dimensional distance measuring module according to claim 11 or 12, wherein the second surface includes a second inclined portion that is inclined to move away from the lens cover as it moves away from the optical axis.
A light source that emits laser light, A lens module including a lens that focuses the light reflected by an object from the irradiated laser beam, an image sensor that receives the light focused by the lens, and a lens barrel that encloses the space between the lens and the image sensor and supports the lens, The lens module and the object are positioned and have a lens cover that is transparent to the wavelength of the laser light, A three-dimensional distance measuring module wherein the third surface of the lens cover facing the lens module includes a third inclined portion that is inclined to move away from the lens module as it moves away from the optical axis of the lens.
When viewed from the direction of the optical axis, The three-dimensional distance measuring module according to claim 14, wherein the third inclined portion is formed over the entire region in which the third inclined portion and the lens module overlap.
The third-dimensional distance measuring module according to claim 14 or 15, wherein the fourth surface of the lens cover facing the object is flat.
When viewed from the direction of the optical axis, The outer shape of the third inclined portion is similar in shape to the outer shape of the image sensor. The degree of inclination of the third inclined portion from a plane perpendicular to the optical axis is positively correlated with the distance between the optical axis and the outer end of the third inclined portion, as described in claim 14 or 15 .
A cavity is provided in the space between the third surface of the lens cover and the fourth surface of the lens cover facing the object. A three-dimensional distance measuring module according to claim 14 or 15, in a cross-sectional view obtained by cutting the lens cover with respect to the plane including the optical axis, the thickness from the third surface to the fourth surface in the direction of the optical axis, excluding the cavity, is constant in the region where the cavity is provided.
The shape of the third surface includes a lens shape, The optical axis of the lens cover coincides with the optical axis of the lens, as described in claim 14 or 15 .
A three-dimensional distance measuring module according to claim 1 , 2, 11, 12, 14, or 15 , The three-dimensional distance measuring module is a three-dimensional distance measuring system having a calculation unit that calculates the distance from the light source to the object based on the travel time of the laser beam.

Description

This disclosure relates to a three-dimensional ranging module and a three-dimensional ranging system. Distancing imaging devices (ToF cameras) that use Time of Flight (ToF) to measure the distance to an object are well known. For example, in Patent Document 1, the ToF camera comprises a three-dimensional distance measuring module having a light source, a lens module, and a lens base that holds the lens module. In this ToF camera, the lens module receives light emitted from the light source, and the distance to the object is measured by calculating the distance from the time difference between illumination and reception. Japanese Patent Publication No. 2019-191173 Figure 1 shows a distance image in which an intensity flare region occurred.Figure 2 is a block diagram showing an example configuration of a three-dimensional distance measuring module according to Embodiment 1.Figure 3 is a top view and two cross-sectional views of a three-dimensional distance measuring module according to Embodiment 1.Figure 4 is an enlarged cross-sectional view of the area around the lens barrel according to Embodiment 1.Figure 5 is a cross-sectional view showing the behavior of laser light according to Embodiment 1.Figure 6 shows the effect on the amount of flare light when the inclination angle of the first inclined section according to Embodiment 1 is changed.Figure 7 is a diagram showing the relationship between the distance between the 3D distance measuring module and an object, and the distance between the 3D distance measuring module and other objects, according to Embodiment 1.Figure 8 is a cross-sectional view showing other behaviors of laser light according to Embodiment 1.Figure 9 is another figure showing the effect on the amount of flare light when the inclination angle of the first inclined section according to Embodiment 1 is changed.Figure 10 is another figure showing the effect on the amount of flare light when the inclination angle of the first inclined section according to Embodiment 1 is changed.Figure 11 is another figure showing the effect on the amount of flare light when the inclination angle of the first inclined section according to Embodiment 1 is changed.Figure 12 is another figure showing the effect on the amount of flare light when the inclination angle of the first inclined section according to Embodiment 1 is changed.Figure 13 is another figure showing the effect on the amount of flare light when the inclination angle of the first inclined portion according to Embodiment 1 is changed.Figure 14 is a diagram illustrating the effect of the first inclined portion being linear according to Embodiment 1.Figure 15 is another diagram illustrating the effect of the first inclined portion being linear according to Embodiment 1.Figure 16 is another diagram illustrating the effect of the first inclined portion being linear according to Embodiment 1.Figure 17 is a top view and two cross-sectional views of a three-dimensional distance measuring module according to a modified example 1 of Embodiment 1.Figure 18 is a top view of the lens barrel and lens, and a cross-sectional view of the lens barrel, according to a modified example 1 of Embodiment 1.Figure 19 shows the relationship between δ and β according to Modification 1 of Embodiment 1.Figure 20 is a top view and two cross-sectional views of a three-dimensional distance measuring module according to a modified example 2 of Embodiment 1.Figure 21 is a cross-sectional view showing the behavior of laser light according to a modified example 2 of Embodiment 1.Figure 22 is a cross-sectional view showing another behavior of laser light according to a modified example 2 of Embodiment 1.Figure 23 is a cross-sectional view of a three-dimensional distance measuring module according to a modified example 3 of Embodiment 1.Figure 24 shows the effect on the amount of flare light when the inclination angle of the first inclined portion is changed in a modified example 3 of Embodiment 1.Figure 25 is another figure showing the effect on the amount of flare light when the inclination angle of the first inclined portion is changed, according to a modified example 3 of Embodiment 1.Figure 26 is another figure showing the effect on the amount of flare light when the inclination angle of the first inclined portion is changed, according to a modified example 3 of Embodiment 1.Figure 27 is another figure showing the effect on the amount of flare light when the inclination angle of the first inclined portion is changed, according to a modified example 3 of Embodiment 1.Figure 28 is another figure showing the effect on the amount of flare light when the inclination angle of the first inclined portion is changed, according to a modified example 3 of Embodiment 1.Figure 29 is a top view and a cross-sectional view of a three-dimensional distance measuring module according to Embodiment 2.Figure 30 shows the effect on the amount of flare light when D, B, H1, and H2 in Embodiment 2 are