阅读说明：本技术 一种雨量传感器的光路结构 (Light path structure of rainfall sensor ) 是由 资桂林 吴平辉 吴柳燕 李建军 于 2020-06-19 设计创作，主要内容包括：本发明公开了一种雨量传感器的光路结构,玻璃的外表面设为玻璃全反射面,光路结构包括有发射源、发射端透镜、若干个双全反射面透镜、接收端透镜、接收元件,双全反射面透镜依次设置,发射源发射红外信号光并射向发射端透镜,红外信号光在发射端透镜中形成射向玻璃全反射面的平行光,平行光依次通过若干个光路单元后再经过玻璃全反射面的全反射最后进入接收端透镜,并在接收端透镜中聚集形成接收信号,接收元件接收接收信号。本发明的雨量传感器的光路结构,利用双全反射面透镜增加玻璃内部全反射区域数量,从而增加感应区域的数量和总面积。在同等感应参数条件下,能够节约元件成本。(The invention discloses an optical path structure of a rainfall sensor, wherein the outer surface of glass is provided with a glass total reflection surface, the optical path structure comprises an emission source, an emission end lens, a plurality of double total reflection surface lenses, a receiving end lens and a receiving element, the double total reflection surface lenses are sequentially arranged, the emission source emits infrared signal light and emits the infrared signal light to the emission end lens, the infrared signal light forms parallel light which emits to the glass total reflection surface in the emission end lens, the parallel light sequentially passes through a plurality of optical path units and then enters the receiving end lens through the total reflection of the glass total reflection surface, the parallel light is gathered in the receiving end lens to form a receiving signal, and the receiving element receives the receiving signal. According to the optical path structure of the rainfall sensor, the number of the total internal reflection areas of the glass is increased by using the double-total-reflection-surface lens, so that the number and the total area of the induction areas are increased. And under the condition of the same induction parameters, the element cost can be saved.)

1. The light path structure of the rainfall sensor is arranged on the inner side of glass, the outer surface of the glass is set as a glass total reflection surface, the light path structure comprises an emission source, an emission end lens, a plurality of double total reflection surface lenses, a receiving end lens and a receiving element, the double total reflection surface lenses respectively comprise a first total reflection surface and a second total reflection surface, the double total reflection surface lenses are sequentially arranged, the emission source emits infrared signal light and emits the infrared signal light to the emission end lens, the infrared signal light forms parallel light which emits to the glass total reflection surface in the emission end lens, the parallel light sequentially passes through a plurality of light path units and then enters the receiving end lens through the total reflection of the glass total reflection surface, the parallel light is collected in the receiving end lens to form a receiving signal, the receiving element receives the receiving signal, and each light path unit sequentially comprises the total reflection of the glass total emission surface, The total reflection of the first total reflection surface and the total reflection of the second total reflection surface.

2. The optical path structure of a rain sensor according to claim 1, wherein the transmitting end lens, the double total reflection surface lens and the receiving end lens are respectively bonded to an inner surface of the glass by silicone.

3. The optical path structure of a rainfall sensor of claim 1, wherein the glass is a flat glass or a curved glass.

4. The optical path structure of a rainfall sensor of claim 1 wherein the transmitting end lens, the double total reflection surface lens and the receiving end lens are all made of PC material.

5. The optical path structure of a rainfall sensor of claim 4, wherein an incident angle of the parallel light entering the first total reflection surface and an incident angle of the parallel light entering the second total reflection surface are respectively larger than a total reflection critical angle of the double total reflection surface lens.

6. The optical path structure of a rainfall sensor of claim 4, wherein the first total reflection surface and the second total reflection surface are mirror surfaces.

Technical Field

The invention belongs to the technical field of rainfall sensors, and particularly relates to a light path structure of a rainfall sensor.

Background

By the end of 2019, the number of automobiles in China reaches 2.6 hundred million, and is increased by 2122 ten thousand and 8.8 percent compared with the number of automobiles at the end of 2018. Along with the improvement of the quality of life of people, the demand for automobiles is continuously increased, and meanwhile, higher requirements are also placed on the functions of the automobiles, and the automobiles are particularly more intelligent.

At present, only a small number of medium-high grade vehicle types are provided with automatic wipers, and the main reason is that the sensors have certain technical barriers and are mastered by large automobile accessory enterprises at home and abroad, so that the selling price is high.

The rainfall sensor adopts an infrared LED as a signal light source, and utilizes a transmitting end lens to collimate and obliquely irradiate infrared signal light emitted by the LED into the front windshield of the automobile. When the obliquely incident signal light meets the angle requirement of the total reflection of the glass, the signal light can be reflected to the receiving end lens and focused and converged on the receiving element through the receiving end lens. When raindrops exist on the upper surface of the windshield, the total reflection condition is destroyed, the infrared signal light is directly emitted from the upper end of the windshield and does not return to the receiving element, the received signal is reduced, the raindrops on the windshield are judged, and the windscreen wiper is started, so that the function of the automatic windscreen wiper is realized.

As shown in fig. 1, a group of elements (emission source 1 and receiving element 2), a pair of lenses (lens 21 and lens 22), a silicone adhesive layer 31 and a glass 41 form an optical path whole, and a sensing region 5 (as shown in fig. 2) is formed on the upper surface of the windshield, and the sensing region directly determines the sensitivity of the sensor, which is one of the most important parameters of the sensor. Therefore, in order to increase the sensitivity, two-transmitter and two-receiver (comprising another set of elements: the emission source 3 and the receiving element 4, the lens 23 and the lens 24 as shown in fig. 1) or two-transmitter and three-receiver, or even one-transmitter and six-receiver are generally provided to increase the number of sensing regions and increase the area of the sensing regions. However, this requires a large number of components, which increases the cost of the sensor.

Disclosure of Invention

In order to solve the technical problems, the invention adopts the technical scheme that: an optical path structure of a rainfall sensor is arranged on the inner side of glass, the outer surface of the glass is a glass total reflection surface, the optical path structure comprises an emission source, an emission end lens, a plurality of double total reflection surface lenses, a receiving end lens and a receiving element, the double total reflection surface lenses respectively comprise a first total reflection surface and a second total reflection surface, the double total reflection surface lenses are sequentially arranged, the emission source emits infrared signal light and emits the infrared signal light to the emission end lens, the infrared signal light forms parallel light which emits to the glass total reflection surface in the emission end lens, the parallel light sequentially passes through a plurality of optical path units and then enters the receiving end lens through the total reflection of the glass total reflection surface, the parallel light is gathered in the receiving end lens to form a receiving signal, the receiving element receives the receiving signal, and each optical path unit sequentially comprises the total reflection of the glass total emission surface, the total reflection of the first, Total reflection of the second total reflection surface.

Preferably, the transmitting end lens, the double total reflection surface lens and the receiving end lens are respectively bonded on the inner surface of the glass through silica gel.

Preferably, in the above technical solution, the glass is a flat glass or a curved glass.

Preferably, the transmitting end lens, the double total reflection surface lens and the receiving end lens are all made of PC materials.

Preferably, in the above technical solution, an incident angle of the parallel light entering the first total reflection surface and an incident angle of the parallel light entering the second total reflection surface are respectively greater than a total reflection critical angle of the double total reflection surface lens.

Preferably, in the above technical solution, the first total reflection surface and the second total reflection surface are mirror surfaces.

The invention has the beneficial effects that: according to the optical path structure of the rainfall sensor, the number of the total internal reflection areas of the glass is increased by using the double-total-reflection-surface lens, so that the number and the total area of the induction areas are increased. And under the condition of the same induction parameters, the element cost can be saved.

Drawings

Fig. 1 is a schematic view of an optical path structure of a conventional rainfall sensor;

fig. 2 is a schematic view of an optical path of a conventional rainfall sensor;

fig. 3 is a schematic view of an optical path structure of the rainfall sensor of the present invention;

FIG. 4 is a schematic view of an optical path structure at another angle of the rainfall sensor of the present invention;

FIG. 5 is a schematic view of the optical path of the rain sensor of the present invention;

FIG. 6 is a schematic view of another optical path of the rain sensor of the present invention;

FIG. 7 is a schematic view of another optical path of the rain sensor of the present invention;

fig. 8 is a schematic view of another optical path structure of the rainfall sensor of the invention.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.