LIQUID LEVEL DETECTION SYSTEM AND LIQUID LEVEL DETECTION METHOD
A liquid level detection system and a liquid level detection method comprising a light source, a light guiding medium, a photoelectric conversion receiver and a processing module is provided. The light guiding medium has an incident surface, a first reflection surface, and an exiting surface. The first reflection surface comprises a first sub-reflection surface and a second sub-reflection surface, with a liquid surface as a boundary line. When the light beam is incident on the first and second sub-reflection surfaces at the same angle, the refraction angle and light intensity loss is different, so there is an abrupt change in the generated light intensity image. The position of the abrupt change is the position of the liquid surface. The position of the liquid surface can thereby be obtained according to the position of abrupt change in light intensity after the light beam passes through the light guiding medium.
1 . A liquid level detection system, comprising:
a light source;
a light guiding medium;
a photoelectric conversion receiver; and
a processing module, wherein:
the light guiding medium has an incident surface, a first reflection surface, and an exiting surface,
the first reflection surface and the exiting surface are both planar,
the first reflection surface intersects a liquid surface,
the first reflection surface comprises a first sub-reflection surface and a second sub-reflection surface, with the liquid surface as a boundary line between the first sub-reflection surface and the second sub-reflection surface,
a light beam emitted by the light source is emitted into the light guiding medium through the incident surface, incident on the first reflection surface, emitted from the light guiding medium through the exiting surface, and incident on the photoelectric conversion receiver,
the light beam is incident at a same angle on the first sub-reflection surface, the second sub-reflection surface, and a boundary between the first sub-reflection surface and the second sub-reflection surface, and
the processing module is configured to generate a light intensity image according to an intensity of the light beam received by the photoelectric conversion receiver and calculate a position of the liquid surface according to a position of an abrupt change in the light intensity image.
2 . The liquid level detection system according to claim 1 , wherein the light beam emitted by the light source is perpendicular to the incident surface.
3 . The liquid level detection system according to claim 1 , wherein the light beam is totally reflected by the first sub-reflection surface and reflected and refracted by the second sub-reflection surface.
4 . The liquid level detection system according to claim 1 , wherein:
the light source is fixedly disposed relative to the light guiding medium, the light beam emitted by the light source is a parallel light, and the light beam is simultaneously incident on the first sub-reflection surface, the second sub-reflection surface, and the boundary between the first sub-reflection surface and the second sub-reflection surface; or
the light source is mounted on a first linear moving mechanism, and the light source is linearly moved relative to the light guiding medium by the first linear moving mechanism to sequentially emit the light beam onto the first sub-reflection surface and the second sub-reflection surface.
5 . The liquid level detection system according to claim 1 , wherein:
the photoelectric conversion receiver is fixedly disposed relative to the light guiding medium, a light beam receiving portion of the photoelectric conversion receiver is planar, and a portion of the light beam reflected by the first sub-reflection surface and a portion of the light beam reflected by the second sub-reflection surface are simultaneously received by the light beam receiving portion; or
the photoelectric conversion receiver is connected to a second linear moving mechanism, and the photoelectric conversion receiver is linearly moved relative to the light guiding medium by the second linear moving mechanism to sequentially receive a portion of the light beam reflected by the first sub-reflection surface and a portion of the light beam reflected by the second sub-reflection surface.
6 . The liquid level detection system according to claim 1 , wherein:
the light guiding medium further has a second reflection surface, and
the light beam is reflected by the second reflection surface prior to being emitted from the light guiding medium through the exiting surface.
7 . The liquid level detection system according to claim 6 , wherein:
the first reflection surface and the second reflection surface are axisymmetric,
an axis of symmetry of the first reflection surface and the second reflection surface is perpendicular to the liquid surface, and
the light beam reflected by the first reflection surface is directed parallel to the liquid surface toward the second reflection surface, wherein the second reflection surface intersects the liquid surface.
8 . The liquid level detection system according to claim 7 , wherein:
the second reflection surface comprises a third sub-reflection surface and a fourth sub-reflection surface, with the liquid surface as the boundary line,
the light beam is totally reflected by the third sub-reflection surface and reflected and refracted by the fourth sub-reflection surface.
9 . The liquid level detection system according to claim 7 , wherein the first reflection surface is perpendicular to the second reflection surface.
10 . The liquid level detection system according to claim 6 , wherein:
the light guiding medium is a right angle isosceles prism,
a first right angle surface of the right angle isosceles prism forms the first reflection surface and a second right angle surface of the right angle isosceles prism forms the second reflection surface, and
the exiting surface and the incident surface are both formed on a hypotenuse of the right angle isosceles prism.
11 . The liquid level detection system according to claim 1 , wherein the incident surface and the exiting surface are on a same plane.
12 . The liquid level detection system according to claim 1 , wherein the light beam in the light guiding medium that is incident on the exiting surface is perpendicular to the exiting surface.
13 . The liquid level detection system according to claim 1 , wherein:
the light guiding medium is a right angle isosceles prism,
a first right angle surface right angle isosceles prism forms the exiting surface and a second right angle surface of the right angle isosceles prism forms the incident surface, and
the first reflection surface is formed on a hypotenuse of the right angle isosceles prism.
14 . A liquid level detection method, comprising:
providing a light guiding medium having an incident surface, a first reflection surface, and an exiting surface, wherein the incident surface, the first reflection surface, and the exiting surface are planar;
positioning the light guiding medium at a liquid surface, the first reflection surface intersecting the liquid surface, wherein the first reflection surface comprises a first sub-reflection surface and a second sub-reflection surface, with the liquid surface as a boundary line between the first sub-reflection surface and the second sub-reflection surface;
emitting a light beam into the light guiding medium through the incident surface, which is then incident on the first reflection surface and emitted from the light guiding medium through the exiting surface, wherein:
the light beam is incident at a same angle at the first sub-reflection surface, the second sub-reflection surface, and a boundary between the first sub-reflection surface and the second sub-reflection surface,
a light intensity image is generated according to an intensity of the light beam emitted from the exiting surface, and
a position of the liquid surface is obtained from a position of an abrupt change in the light intensity image.
15 . The liquid level detection method according to claim 14 , wherein the light beam is totally reflected by the first sub-reflection surface and reflected and refracted by the second sub-reflection surface.
16 . The liquid level detection method according to claim 15 , wherein:
the light guiding medium further has a second reflection surface,
the second reflection surface intersects the liquid surface,
the second reflection surface comprises a third sub-reflection surface and a fourth sub-reflection surface, with the liquid surface as a boundary line between the third sub-reflection surface and the fourth sub-reflection surface,
a portion of the light beam that is reflected by the first sub-reflection surface is totally reflected by the third sub-reflection surface and is then incident on the exiting surface, and
a portion of the light beam that is reflected by the second sub-reflection surface is reflected and refracted by the fourth sub-reflection surface, and a portion of the light beam reflected by the fourth sub-reflection surface is directed toward the exiting surface.
17 . The liquid level detection method according to claim 14 , wherein the exiting surface and the incident surface are both disposed parallel to the liquid surface.
18 . The liquid level detection method according to claim 17 , wherein:
the light beam is incident on the light guiding medium perpendicular to the incident surface, and
the light beam emitted through the exiting surface is perpendicular to the incident surface.
19 . The liquid level detection method according to claim 14 , wherein:
the light beam is simultaneously incident on the first sub-reflection surface, the second sub-reflection surface, and the boundary between the first sub-reflection surface and the second sub-reflection surface; or
the light beam is movably emitted onto the first sub-reflection surface and the second sub-reflection surface in sequence.
20 . (canceled)
21 . A liquid level detection system, comprising:
a light source;
a light guiding medium;
a photoelectric conversion receiver; and
a processing module, wherein:
the light guiding medium has an incident surface, a first reflection surface, and an exiting surface,
the first reflection surface intersects a liquid surface when the light guiding medium is disposed within a liquid,
the first reflection surface comprises a first sub-reflection surface and a second sub-reflection surface, with the liquid surface as a boundary line between the first sub-reflection surface and the second sub-reflection surface,
the processing module is configured to:
generate a light intensity image according to an intensity of a light beam emitted onto the light guiding medium and received by the photoelectric conversion receiver, and
calculate a position of the liquid surface according to a position of an abrupt change in the light intensity image due to difference in intensity of a portion of the light beam reflected by the first sub-reflection surface and received by the photoelectric conversion receiver and a portion of the light beam reflected by the second sub-reflection surface and received by the photoelectric conversion receiver.