Patent Publication Number: US-2023152219-A1

Title: Optical water-quality detection apparatus

Description:
This application claims the benefit of Taiwan application Serial No. 110142782, filed Nov. 17, 2021, the subject matter of which is incorporated herein by reference. 
     TECHNICAL FIELD 
     The disclosure relates in general to an optical water-quality detection apparatus. 
     BACKGROUND 
     In response to needs for water quality testing, building water quality detection apparatus is necessary. In the storage tank for water quality detection, microorganism attachment or growth is often formed on a tank wall to produce biofilm which causes obvious interference to the water quality detection. Therefore, frequent cleaning is required to maintain the accuracy and stability of the detection results. However, the maintenance costs and manpower burden on the operator. 
     SUMMARY 
     According to an embodiment, an optical water-quality detection apparatus is provided. The optical water-quality detection apparatus includes a detection chamber device, a biofilm-inhibited light source, a detection light source and a first sensor. The detection chamber device includes a detection chamber. The biofilm-inhibited light source is disposed outside the detection chamber and configured to emit an inhibition light. The detection light source is disposed outside the detection chamber and configured to emit a detection light. The first sensor is configured to sense the detection light penetrating the detection chamber. Wherein a beam of the detection light and a beam of the inhibition light overlap each other when penetrating the detection chamber. 
     The above and other aspects of the disclosure will become better understood with regard to the following detailed description of the preferred but non-limiting embodiment (s). The following description is made with reference to the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    shows a schematic diagram of an optical path of the optical water-quality detection apparatus according to an embodiment of the disclosure; 
         FIG.  2 A  shows a schematic diagram of the optical path of the optical water-quality detection apparatus according to another embodiment of the disclosure; 
         FIG.  2 B  shows a diagram of a working mode of the optical water-quality detection apparatus of  FIG.  2 A ; 
         FIG.  3    shows a schematic diagram of the optical path of an optical water-quality detection apparatus according to another embodiment of the disclosure; 
         FIG.  4    shows a schematic diagram of the optical path of an optical water-quality detection apparatus according to another embodiment of the disclosure; 
         FIG.  5    shows a schematic diagram of an optical water-quality detection apparatus according to another embodiment of the disclosure; 
         FIG.  6    shows a schematic diagram of a cross-sectional view of the optical water-quality detection apparatus of  FIG.  5    along the direction  6 - 6 ′; 
         FIG.  7    shows a schematic diagram of the holder of  FIG.  5    releasing the fixing relationship between the detection chamber device and the sensing base; 
         FIG.  8    shows a schematic diagram of the detection chamber device and the sensing base of  FIG.  7   ; 
         FIG.  9    shows a schematic diagram of a cross-sectional view of a detection chamber device of an optical water-quality detection apparatus according to another embodiment of the disclosure; and 
         FIG.  10    shows a schematic diagram of an experimental result of the optical water-quality detection apparatus according to the embodiment of the disclosure. 
     
    
    
     In the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the disclosed embodiments. It will be apparent, however, that one or more embodiments could be practiced without these specific details. In other instances, well-known structures and devices are schematically shown in order to simplify the drawing. 
     DETAILED DESCRIPTION 
     Referring to  FIG.  1   ,  FIG.  1    shows a schematic diagram of an optical path of the optical water-quality detection apparatus  100 ′ according to an embodiment of the disclosure. The optical water-quality detection apparatus  100 ′ includes a detection chamber device  100 A, a biofilm-inhibited light source  110 , a detection light source  120 , a first sensor  130  and a first light-splitting mirror  140 . The detection chamber device  100 A includes a detection chamber R 1 . The biofilm-inhibited light source  110  is disposed outside the detection chamber R 1  and configured to emit inhibition light L 1 . The detection light source  120  is disposed outside the detection chamber R 1  and configured to emit detection light L 2 . The first sensor  130  is configured to sense the detection light L 2  after the detection light L 2  penetrates the detection chamber R 1 . The beam of the detection light L 2  and the beam of the inhibition light L 1  overlap each other when they travel within the detection chamber R 1 . For example, the beam of the detection light L 2  has a spot area (a cross-sectional area of a beam diameter D 2 ) is less than or equal to another spot area (a cross-sectional area of a beam diameter D 1 ) of the beam of the inhibition light L 1 , and the spot area of the detection light L 2  completely overlap the spot area of the inhibition light L 1 . As a result, while a to-be-tested liquid (not shown) in the detection chamber R 1  is under detection, the inhibition light L 1  could inhibit the activity of the biofilm, and accordingly it could avoid the detection accuracy effected by biofilm and maintain a proper detection accuracy longer. 
     As shown in  FIG.  1   , the detection chamber R 1  is hollow, for example. The detection chamber device  100 A has a liquid storage space R 11  disposed within the detection chamber R 1 , and the liquid storage space R 11  could receive the to-be-tested liquid. The detection light L 2  penetrates the detection chamber R 1  through the to-be-tested liquid. The to-be-tested liquid is, for example, drinking water, factory wastewater, stream water, agricultural channel water, rainwater or other liquids that require to be tested. The detection chamber R 1  includes a light-incident side R 1   a  and a light-exit side R 1   b , and the inhibition light L 1  and the detection light L 2  is incident into the liquid storage space R 11  through the light-incident side R 1   a  and leave the liquid storage space R 11  through the light-exit side R 1   b . The inhibition light L 1  and the detection light L 2  penetrate the liquid storage space R 11  could inhibit the activity of the biofilm, slow down growth rate of the biofilm on a surface, prolong operation life cycle of the optical water-quality detection apparatus  100 ′ and/or increase or stabilize the detection accuracy. In addition, since the beam of the detection light L 2  overlaps the beam of the inhibition light L 1 , the biofilm could be inhibited by the inhibition light L 1  within the range of the beam diameter of the detection light L 2 . 
     Referring to  FIGS.  2 A to  2 B .  FIG.  2 A  shows a schematic diagram of the optical path of the optical water-quality detection apparatus  100  according to another embodiment of the disclosure, and  FIG.  2 B  shows a diagram of a working mode of the optical water-quality detection apparatus  100  of  FIG.  2 A . 
     The optical water-quality detection apparatus  100  includes the detection chamber device  100 A, two detection windows  105 , the biofilm-inhibited light source  110 , the detection light source  120 , the first sensor  130 , the first light-splitting mirror  140 , a first condensing lens  150  and a second condensing lens  160 . 
     The detection chamber device  100 A includes the detection chamber R 1 . The biofilm-inhibited light source  110  is disposed outside the detection chamber R 1  and configured to emit inhibition light L 1 . The detection light source  120  is disposed outside the detection chamber R 1  and configured to emit detection light L 2 . The first sensor  130  is configured to sense the detection light L 2  after the detection light L 2  penetrates the liquid storage space R 11 . The beam of the detection light L 2  and the beam of the inhibition light L 1  overlap each other during penetrating the liquid storage space R 11 . For example, the spot area (the cross-sectional area of the beam diameter D 2 ) of the beam of the detection light L 2  is less than or equal to the spot area (the cross-sectional area of the beam diameter D 1 ) of the beam of the inhibition light L 1 , and the spot area of the detection light L 2  is completely (or entirely) overlapped with the spot area of the inhibition light L 1 . 
     The detection light L 2  penetrates the liquid storage space R 11  through the to-be-tested liquid. The to-be-tested liquid in the liquid storage space R 11  contacts the detection window  105 , and the biofilm is formed on the surface of the detection window  105 . The biofilm is structured community formed by Exopoly Saccharides (EPS) generated by the microbial cell itself surrounding the microbial cell and the attaching to an inert or biofilm surface immersed in liquid. The biofilms could include many different kinds of microorganisms, such as bacteria, archaea, protozoa, fungi, algae, etc. 
     The detection chamber R 1  includes the light-incident side R 1   a  and the light-exit side R 1   b , and the inhibition light L 1  and the detection light L 2  enter the liquid storage space R 11  through the light-incident side R 1   a  and leave the liquid storage space R 11  through the light-exit side R 1   b . The detection window  105  is, for example, glass, such as quartz glass. The two detection windows  105  are light-transmissive and respectively disposed on two opposite sides of the detection chamber R 1 , for example, the light-incident side R 1   a  and the light-exit side R 1   b . The inhibition light L 1  and the detection light L 2  penetrate the liquid storage space R 11  through the detection windows  105  for inhibiting the activity of the biofilm on the detection window  105 , slowing down the growth of the biofilm on the surface of the detection window  105  and prolonging the operation life cycle of the optical water-quality detection apparatus  100  and/or increasing or stabilize detection accuracy. In addition, since the beam of the detection light L 2  overlaps the beam of the inhibition light L 1 , the biofilm on the detection window  105  could be inhibited by the inhibition light L 1  within the range of the beam diameter of the detection light L 2 . 
     In an embodiment, the biofilm-inhibited light source  110  is, for example, an ultraviolet light source, the inhibition light L 1  has a center wavelength, for example, 275 nanometers (nm), the detection light source  120  is, for example, a halogen light source having a wide wavelength range, and the detection light L 2  is, for example, visible light-near infrared light (VIS-NIR). The first sensor  130  could react to the detection light L 2  and generate signal, but does not react to the inhibition light L 1 . For example, a filter (not shown in  FIG.  2 A ) could be disposed in front of the first sensor  130  to filter out the signal of the inhibition light L 1 . Alternatively, the corresponding photo sensor could be selected according to the wavelength range of the detection light L 2 . For example, for the UV spectrum, gallium nitride photodiodes could be selected, and/or, for visible light to near-infrared light, silicon photodiodes could be selected. As a result, the optical water-quality detection apparatus  100  could detect a specific composition of the to-be-tested liquid in the liquid storage space R 11  by the detection light L 2 . 
     In an embodiment, the first sensor  130  is, for example, a silicon photodiode (Si PD), and the first light-splitting mirror  140  could reflect light having a center wavelength of 850 nm, so the detection light L 2  incident into the first sensor  130  has the center wavelength of 850 nm. The first sensor  130  could react to the detection light L 2  having the center wavelength of 850 nm and generate signal so as to detect Suspended Solids (SS) of the to-be-tested liquid in the liquid storage space R 11 , and such test is called “SS detection”. In another embodiment, the first sensor  130  could react to light having the center wavelength of 546 nm, 650 nm or combination thereof and generate signal, or the first sensor  130  could react to light be partially absorbed or scattered by suspended solids in the to-be-tested liquid for performing SS detection. In another embodiment, the first light-splitting mirror  140  could reflect light having the center wavelength of 450 nm, and thus the detection light L 2  incident into the first sensor  130  has the center wavelength of 450 nm. The first sensor  130  could react to the detection light L 2  having the center wavelength of 450 nm and generate signal so as to detect concentration of copper ion of the to-be-tested liquid in the liquid storage space R 11 , and such detection is called “copper ion concentration detection”. 
     As shown in  FIG.  2 A , in terms of relative positional relationship, the biofilm-inhibited light source  110 , the detection light source  120 , the first light-splitting mirror  140 , the first condensing lens  150  and the second condensing lens  160  are disposed on a side of the detection chamber R 1 , such as the light-incident side R 1   a , and the first sensor  130  is disposed on the opposite side of the detection chamber R 1 , such as the light-exit side R 1   b.    
     As shown in  FIG.  2 A , the first light-splitting mirror  140  is disposed between the biofilm-inhibited light source  110  and the detection chamber R 1 , or disposed between the detection light source  120  and the detection chamber R 1 , and is configured to guide the inhibition light L 1  and the detection light L 2  enter the liquid storage space R 11 . The first light-splitting mirror  140  is, for example, a dichroic beam splitter, wherein the first light-splitting mirror  140  allows the inhibition light L 1  to travel through but reflects the detection light L 2 . As a result, the inhibition light L 1  and the detection light L 2  together (or at the same time) could be incident into the first sensor  130  from the first light-splitting mirror  140  after being traveling to the first light-splitting mirror  140  in different directions. 
     As shown in  FIG.  2 A , the first condensing lens  150  and the biofilm-inhibited light source  110  are disposed opposite to each other. The first condensing lens  150  is configured to adjust the beam diameter D 1  of the inhibition light L 1 . The second condensing lens  160  and the detection light source  120  are opposite to each other. The second condensing lens  160  is configured to adjust the beam diameter D 2  of the detection light L 2 . As a result, due to the design of the first condensing lens  150  and the second condensing lens  160 , the beam of the detection light L 2  could overlap the beam of the inhibition light L 1 . In an embodiment, the first condensing lens  150  is, for example, a single lens or a lens group formed by gluing several lenses to each other. The aforementioned lens could include a plano-convex lens, a convex plano lens or other type of light-transmissive lens that could change the beam diameter D 1  of the inhibition light L 1 . The second condensing lens  160  has the structure similar to or the same as that of the first condensing lens  150 , and the similarities will not be repeated here. As long as the beam diameter D 2  of the detection light L 2  could change, the embodiment of the disclosure does not limit the structure of the second condensing lens  160 . 
     In addition, in the embodiment, the first condensing lens  150  and the biofilm-inhibited light source  110  could be disposed separately (that is, without physical connection). Alternatively, the first condensing lens  150  and the biofilm-inhibited light source  110  are directly connected. Similarly, the second condensing lens  160  and the detection light source  120  could disposed separately (that is, without physical connection). Alternatively, the second condensing lens  160  and the detection light source  120  are directly connected. 
     As shown in  FIG.  2 B , ST represents the warm-up time of the light source, WT represents the illuminating time (ON) of the light source, CT represents the non-illuminating time (OFF) of the light source, and T represents a work period. The warm-up time could speed up the light source to enter the stable period, provide stability in the work execution, and reduce the required working time. The light source does not emit light during the non-illuminating time CT, and the light source is cooled. In the embodiment, the illuminating time WT immediately follows the warm-up time ST. However, in another embodiment, the illuminating time WT and the warm-up time ST could be separated from each other, that is, a non-illuminating time is inserted between the warm-up time ST and the illuminating time WT. Although not shown, the working modes of the biofilm-inhibited light source  110  and the detection light source  120  could be controlled by a processor (not shown), and such processor could be electrically connected to the light source and/or sensor herein to control the operation of these components, and receive and/or analyze the signal from the sensor. 
     The working sequence of the biofilm-inhibited light source  110  and the detection light source  120  could be the same or different. For example, for the biofilm-inhibited light source  110 , WT:CT:ST=1:4:10. In a preferred embodiment, WT:CT:ST=10 millisecond (ms):40 ms:100 ms. For the detection light source  120  (for example, halogen lamp), WT:CT:ST=1:3:4. In a preferred embodiment, WT:CT:ST=250 ms:750 ms:1000 ms, but the embodiments of the disclosure are not limited thereto. 
     The working frequencies of the biofilm-inhibited light source  110  and the detection light source  120  could be the same or different. For example, for the biofilm-inhibited light source  110 ,  80  work period T could be executed every 20 minutes; however, such exemplification is not meant to be for limiting. For the detection light source  120  (for example, halogen lamp),  5  work period T could be executed every 20 minutes; however, such exemplification is not meant to be for limiting. In the embodiment, one illuminating time WT and one non-illuminating time CT are defined as one work period T. Although not shown, the aforementioned illuminating time WT, the non-illuminating time CT and/or warm-up time ST could also be controlled by the processor. 
     In addition, the working mode of the optical water-quality detection apparatus in other embodiments of the disclosure is the same as that shown in  FIG.  2 A , and the similarities will not be repeated here. 
     Referring to  FIG.  3   ,  FIG.  3    shows a schematic diagram of the optical path of an optical water-quality detection apparatus  200  according to another embodiment of the disclosure. The optical water-quality detection apparatus  200  includes a detection chamber device  200 A, two detection windows  105 , a biofilm-inhibited light source  210 , a sensor  230  and a first condensing lens  250 . The optical water-quality detection apparatus  200  has the technical features similar to or the same as that of the optical water-quality detection apparatus  100  expect that the optical water-quality detection apparatus  200  could omit the detection light source  120 , the first light-splitting mirror  140  and the second condensing lens  160 . 
     In the embodiment, the biofilm-inhibited light source  210  is configured to emit an inhibition light L 1 ′ which also has the detection function of the aforementioned detection light L 2 . In an embodiment, the biofilm-inhibited light source  210  is, for example, an ultraviolet light source, the inhibition light L 1 ′ has the center wavelength of, for example, 275 nm. The sensor  230  is, for example, a gallium nitride (GaN) sensor which could react to the inhibition light L 1 ′ after the inhibition light L 1 ′ penetrates the liquid storage space R 11 , and generate signal so as to detect the chemical oxygen demand (COD) of the to-be-tested liquid in the liquid storage space R 11 . Such detection optical path is called the “COD detection optical path”. The biofilm-inhibited light source  210  has a center wavelength which is selected from 250 nm, 254 nm or combination thereof or other spectrum which could be absorbed by organic matters in the to-be-tested liquid for performing COD detection. Although not shown, the detection result could be transmitted to an external electronic device through a wireless communication module, and such electronic device could display a trend of the detection result over a period of time (water-quality monitoring). 
     As shown in  FIG.  3   , the first condensing lens  250  and the biofilm-inhibited light source  210  are disposed opposite to each other. The first condensing lens  250  is configured to adjust the beam diameter D 1 ′ of the inhibition light L 1 ′. In an embodiment, the first condensing lens  250  and the biofilm-inhibited light source  210  could be configured separately (that is, without physical connection). Alternatively, the first condensing lens  250  and the biofilm-inhibited light source  210  are directly connected. 
     As shown in  FIG.  3   , in terms of relative positional relationship, the biofilm-inhibited light source  210  and the first condensing lens  250  could be disposed on a side of the detection chamber R 1 , such as the light-incident side R 1   a , and the sensor  230  could be disposed on the opposite side of the detection chamber R 1 , such as the light-exit side R 1   b.    
     Referring to  FIG.  4   ,  FIG.  4    shows a schematic diagram of the optical path of an optical water-quality detection apparatus  300  according to another embodiment of the disclosure. The optical water-quality detection apparatus  300  includes a detection chamber device  300 A, two detection windows  105 , the biofilm-inhibited light source  110 , the detection light source  120 , the first sensor  330 , the first light-splitting mirror  140 , the first condensing lens  150 , the second condensing lens  160 , a second light-splitting mirror  340  and a second sensor  370 . The optical water-quality detection apparatus  300  has technical features similar to or the same as that of the optical water-quality detection apparatus  100  expect that the optical water-quality detection apparatus  300  further includes the second light-splitting mirror  340  and the second sensor  370 . 
     As shown in  FIG.  4   , the first sensor  330  is, for example, a GaN detector which could react to the inhibition light L 1  after the inhibition light L 1  penetrates the detection chamber R 1  and generate signal so as to sense the chemical oxygen demand of the to-be-tested liquid in the liquid storage space R 11 . 
     In the embodiment, the same beam of the detection light L 2  could detect a variety of different properties of the to-be-tested liquid in the liquid storage space R 11 , and it will be further described below. 
     As shown in  FIG.  4   , the second sensor  370  is located outside the detection chamber R 1 . The second light-splitting mirror  340  is located outside the detection chamber R 1  and adjacent to the light-exit side R 1   b  to guide the detection light L 2  to the second sensor  370 . The second light-splitting mirror  340  is, for example, a dichroic beam splitter which allows the inhibition light L 1  to travel through but reflects the detection light L 2 , for example, the first waveband light L 21  of the reflection detection light L 2 . The second sensor  370  is configured to generate signal by reacting to the first waveband light L 21  so as to detect a specific composition of the to-be-tested liquid in the liquid storage space R 11 . In an embodiment, the second sensor  370  is, for example, a silicon photodiode, and the second light-splitting mirror  340  could reflect light with a center wavelength of 850 nm, so the first waveband light L 21  incident into the second sensor  370  includes the center wavelength of 850 nm. The second sensor  370  could react to the first waveband light L 21  and generates signal so as to detect suspended solids within the to-be-tested liquid in the liquid storage space R 11  (SS detection). In another embodiment, the second light-splitting mirror  340  could reflect light with a center wavelength of 450 nm, so the first waveband light L 21  incident into the second sensor  370  includes the center wavelength of 450 nm. The second sensor  370  could react to the first waveband light L 21  and generates signal so as to detect the concentration of copper ions of the to-be-tested liquid in the liquid storage space R 11 . 
     As shown in  FIG.  4   , in terms of relative positional relationship, the biofilm-inhibited light source  110 , the detection light source  120 , the first light-splitting mirror  140 , the first condensing lens  150  and the second condensing lens  160  could be disposed on a side of the detection chamber R 1 , such as the light-incident side R 1   a , and the first sensor  330 , the second light-splitting mirror  340  and the second sensor  370  could be disposed on the opposite side of the detection chamber R 1 , such as the light-exit side R 1   b.    
     Referring to  FIGS.  5  to  6   .  FIG.  5    shows a schematic diagram of an optical water-quality detection apparatus  400  according to another embodiment of the disclosure, and  FIG.  6    shows a schematic diagram of a cross-sectional view of the optical water-quality detection apparatus  400  of  FIG.  5    along the direction  6 - 6 ′. The optical water-quality detection apparatus  400  includes a detection chamber device  400 A, a sensing base  400 B, a detection chamber device  400 A, two detection windows  105 , the biofilm-inhibited light source  110 , the detection light source  120 , the first sensor  130 , and the first light-splitting mirror  140 , the first condensing lens  150 , the second condensing lens  160 , the biofilm-inhibited light source  210 , the first condensing lens  250 , the sensor  230 , a first filter  435  and a holder  440 . 
     As shown in  FIGS.  5  and  6   , the detection chamber device  400 A includes a liquid storage space R 11  within the detection chamber R 1 , two detection windows  105 , a liquid inlet  400 A 1 , an overflow outlet  400 A 2 , a reagent inlet  400 A 3 , and the liquid outlet  400 A 4 . The two detection windows  105  are disposed on two opposite sides of the detection chamber R 1 . The liquid inlet  400 A 1 , the overflow outlet  400 A 2 , the reagent inlet  400 A 3  and the liquid outlet  400 A 4  are communicated with the liquid storage space R 11 . The liquid inlet  400 A 1  is disposed within the detection chamber R 1  and communicated with the liquid storage space R 11 , and the to-be-tested liquid could enter the liquid storage space R 11  from the liquid inlet  400 A 1 . A reagent (not shown) could enter the liquid storage space R 11  from the reagent inlet  400 A 3  to be mixed with the to-be-tested liquid. For example, when performing copper ion concentration detection, the copper ion reagent could flow into the liquid storage space R 11  from the reagent inlet  400 A 3  to be mixed with the to-be-tested liquid. When the to-be-tested liquid contains copper ions of different concentrations, the mixed solution will show a color change in chromaticity. The overflow outlet  400 A 2  communicates with the liquid storage space R 11  and has a central axis X 1 . The central axis X 1  of the overflow outlet  400 A 2  is located between the detection windows  105  and the reagent inlet  400 A 3  for allowing the redundant to-be-tested liquid to be discharged. As a result, the to-be-tested liquid in the liquid storage space R 11  could be maintained at a fixed volume (constant). In addition, when the quantitative copper ion reagent flows into the liquid storage space R 11 , the mixture of the to-be-tested liquid and the copper ion reagent could have a fixed ratio composition for ensuring the accuracy of the copper ion concentration detection. In addition, the liquid outlet  400 A 4  is located at a bottom surface or a bottom portion of the detection chamber device  400 A, and the to-be-tested liquid in the liquid storage space R 11  could be discharged out of the detection chamber R 1  through the liquid outlet  400 A 4 . When the to-be-tested liquid is under detection, the drainage port  400 A 4  could be closed or plugged for preventing the to-be-tested liquid from being discharged. 
     At least one optical element of the aforementioned optical water-quality detection apparatus could be disposed on the sensing base  400 B. For example, the optical elements of the aforementioned optical water-quality detection apparatus  100  (for example, the biofilm-inhibited light source  110 , the detection light source  120 , the first sensor  130 , the first light-splitting mirror  140 , the first condensing lens  150  and the second condensing lens  160 ) and the optical elements (for example, the biofilm-inhibited light source  210 , the first condensing lens  250  and the sensor  230 ) of the optical water-quality detection apparatus  200  could be disposed on the sensing base  400 B. The sensing base  400 B of the embodiment of the disclosure includes, for example, the optical water-quality detection apparatus  100  and  200 ; however, such exemplification is not meant to be for limiting. 
     As shown in  FIG.  6   , in the embodiment, the biofilm-inhibited light source  110  and the first condensing lens  150  are integrated into one piece. For example, the biofilm-inhibited light source  110  and the first condensing lens  150  directly connected with each other, or separated from each other (for example, that is, without physical connection). Similarly, the biofilm-inhibited light source  210  and the first condensing lens  250  are integrated into one piece. For example, the biofilm-inhibited light source  210  and the first condensing lens  250  directly connected with each other, or separated from each other (for example, that is, without physical connection). In an embodiment, the first condensing lens  150  could be a hemispherical lens having a first diameter, and the second condensing lens  160  could also be a hemispherical lens having a second diameter, and the first diameter is greater than or equal to the second diameter. The biofilm-inhibited light sources  110  and  210  could be disposed on a focus of the first condensing lens  150  and  250 . Similarly, the detection light source  120  is disposed on a focus of the second condensing lens  160 , so that the light emitted from the inhibition light source and the detection light source form parallel beams after traveling through these condensing lenses. 
     The first filter  435  is disposed between the first sensor  130  and the first light-splitting mirror  140 . The first filter  435  and the first sensor  130  could contact directly, but could also be spaced apart from each other without contacting. The first filter  435  could allow a portion, having a specific wavelength, of the detection light L 2  to travel through (but block the other portion of the detection light L 2 ), thereby increasing the detection accuracy of the first sensor  130  for a specific composition. For example, when performing “SS detection”, the first filter  435  could allow a portion, having the center wavelength of 850 nm, of the detection light L 2  to travel through (but block the other portion, having the wavelength rather than the center wavelength of 850, of the detection light L 2 ), thereby increasing the detection accuracy of the first sensor  130  for the suspended solids of the to-be-tested liquid in the liquid storage space R 11 . In another example, when performing “copper ion concentration detection”, the first filter  435  could allow a portion, having the center wavelength of 450 nm, of the detection light L 2  to travel through (but block the other portion, having the wavelength rather than the center wavelength of 450 nm, of the detection light L 2 ), thereby increasing the detection accuracy of the first sensor  130  for the concentration of copper ions of the to-be-tested liquid in the liquid storage space R 11 . 
     In summary, the optical water-quality detection apparatus  400  provides two sets of independent detection optical paths, one set of the detection optical paths could perform a variety of different detections, for example, the SS detection and the copper ion concentration detection, and the other set of the detection optical paths could perform single detection, for example, COD detection. 
     In addition, the working sequence of the light sources in  FIG.  6    could be the detection light source  120  (SS detection), the biofilm-inhibited light source  210  (COD detection) and the biofilm-inhibited light source  110  (biofilm inhibition) in sequence; however, such exemplification is not meant to be for limiting. 
     In addition, the sensing base  400 B is detachably assembled with the detection chamber device  400 A. As shown in  FIG.  5   , the holder  440  could detachably fixes the relative position of the detection chamber device  400 A and the sensing base  400 B, so that the sensing base  400 B is detachably assembled with the detection chamber device  400 A, so that the detection chamber device  400 A could be quickly replaced with another detection chamber device  400 A. In an embodiment, the holder  440  is, for example, an element having threaded. 
     Referring to  FIGS.  7  to  8   .  FIG.  7    shows a schematic diagram of the holder  440  of  FIG.  5    releasing the fixing relationship between the detection chamber device  400 A and the sensing base  400 B, and  FIG.  8    shows a schematic diagram of the detection chamber device  400 A and the sensing base  400 B of  FIG.  7   . The detection chamber device  400 A and the sensing base  400 B are detachably connected. As shown in  FIG.  7   , when the holder  440  is released from the detection chamber device  400 A and the sensing base  400 B, the fixing relationship between the detection chamber device  400 A and the sensing base  400 B could be released. As shown in  FIG.  8   , when the fixed relationship between the detection chamber device  400 A and the sensing base  400 B is released, the detection chamber device  400 A and the sensing base  400 B could be separated. As a result, the disassembled detection chamber device  400 A could be replaced with a new detection chamber device  400 A (for example, the new detection chamber device  400 A includes clean detection window  105 ) conveniently and quickly. 
     Referring to  FIGS.  8  to  9   ,  FIG.  9    shows a schematic diagram of a cross-sectional view of a detection chamber device  400 A of an optical water-quality detection apparatus  500  according to another embodiment of the disclosure. The optical water-quality detection apparatus  500  includes the detection chamber device  400 A, the sensing base  400 B, at least one detection window  105 , the biofilm-inhibited light source  110 , the detection light source  120 , the first sensor  330 , the first light-splitting mirror  140 , and the first condensing lens  150 , the second condensing lens  160 , the second light-splitting mirror  340 , the second sensor  370 , the third light-splitting mirror  540 , the third sensor  570 , the first filter  581 , the second filter  582  and the third filter  583 . 
     The optical elements of the aforementioned optical water-quality detection apparatus could be disposed on the sensing base  400 B. For example, the optical elements of the aforementioned optical water-quality detection apparatus  300  (for example, the biofilm-inhibited light source  110 , the detection light source  120 , the first sensor  330 , the first light-splitting mirror  140 , the first condensing lens  150 , the second condensing lens  160 , the second light-splitting mirror  340  and the second sensor  370 ) are disposed on the sensing base  400 B. In addition, the third light-splitting mirror  540 , the third sensor  570 , the first filter  581 , the second filter  582  and the third filter  583  are also disposed on the sensing base  400 B. 
     The second light-splitting mirror  340  is located outside the detection chamber R 1  of the detection chamber device  400 A and adjacent to the light-exit side R 1   b , and is configured to guide the first waveband light L 21  of the detection light L 2  to the second sensor  370 . The third light-splitting mirror  540  is located outside the detection chamber R 1  and adjacent to the light-exit side R 1   b , and is configured to guide the second waveband light L 22  of the detection light L 2  to the third sensor  570 , wherein the first waveband light L 21  has the wavelength different from that of the second waveband light L 22 . As a result, the second sensor  370  and the third sensor  570  could respectively react to different waveband light of the detection light L 2  so as to detect several different types of characteristics of the to-be-tested liquid in the detection chamber R 1 . 
     In an embodiment, the second light-splitting mirror  340  could reflect light having the central wavelength of 850 nm, and accordingly the wavelength of the first waveband light L 21  includes the central wavelength of 850 nm. The second sensor  370  could react to the first waveband light L 21  and generate signal so as to detect the suspended solids of the test liquid in the detection chamber R 1 . The second filter  582  is disposed between the second sensor  370  and the second light-splitting mirror  340 , and could allow the first waveband light L 21 , having the center wavelength of 850 nm, of the detection light L 2  to travel through (but block the waveband light, having the wavelength rather than the center wavelength of 850 nm, of the detection light L 2 ), thereby increasing the detection accuracy of the second sensor  370  for the suspended solids of the to-be-tested liquid in the liquid storage space R 11 . 
     The third light-splitting mirror  540  is, for example, a dichroic mirror, which allows the inhibition light L 1  to travel through, but reflects the detection light L 2 , for example, the second waveband light L 22  of the reflection detection light L 2 . In an embodiment, the third light-splitting mirror  540  could reflect light having the center wavelength of 450 nm, and thus the wavelength of the second waveband light L 22  includes the center wavelength of 450 nm. The third sensor  570  could react to the second waveband light L 22  and generate signal so as to detect the concentration of copper ions of the to-be-tested liquid in the detection chamber R 1 . The third filter  583  could be disposed between the third sensor  570  and the third light-splitting mirror  540 , and could allow or only allow the second waveband light L 22 , having the center wavelength of 450 nm, of the detection light L 2  to travel through (but block the waveband light, having the wavelength rather than the center wavelength of 450 nm, of the detection light L 2 ), thereby increasing the detection accuracy of the third sensor  570  for the concentration of copper ions of the to-be-tested liquid in the liquid storage space R 11 . 
     As shown in  FIG.  9   , the second light-splitting mirror  340  is disposed between the detection chamber R 1  and the third light-splitting mirror  540 , and the detection light L 2  travels through the second light-splitting mirror  340  and the third light-splitting mirror  540  in sequence. Furthermore, the first waveband light L 21  of the detection light L 2  is first reflected by the second light-splitting mirror  340  to the second sensor  370 . Then, the other waveband light (having a shorter wavelength than the first waveband light L 21 ) of the detection light L 2  is incident into the third light-splitting mirror  540  after traveling through the second light-splitting mirror  340 . In the other waveband light of the detection light L 2 , the second waveband light L 22  whose wavelength is shorter than the first waveband light L 21  is reflected by the third light-splitting mirror  540  to the third sensor  570 . Then, the waveband, rather than the first waveband light L 21  and the second waveband light L 22 , of the detection light L 2  (hereinafter referred to as a third waveband light L 23  whose wavelength is shorter than the first waveband light L 21  and the second waveband light L 22 ) continue to be incident into the first sensor  330 . 
     The second light-splitting mirror  340  and the third light-splitting mirror  540  are disposed between the detection chamber R 1  and the first sensor  330 . As a result, after penetrating the detection chamber R 1 , the third waveband light L 23  of the detection light L 2  travels through the second light-splitting mirror  340  and the third light-splitting mirror  540  to the first sensor  330  in sequence. 
     In an embodiment, the center wavelength of the third wavelength band light L 23  is, for example, 275 nm. The first sensor  330  is, for example, a GaN detector, which could react to the third waveband light L 23  after the third waveband light L 23  penetrates the detection chamber R 1  and generate signal so as to detect the chemical oxygen demand of the to-be-tested liquid in the liquid storage space R 11 . The first filter  581  is disposed between the first sensor  330  and the third light-splitting mirror  540 , and could allow the waveband light, having the center wavelength of 275 nm, of the detection light L 2  to travel through but block the waveband light, having the wavelength rather than the center wavelength of 450 nm, of the detection light L 2 ), thereby increasing the detection accuracy of the first sensor  130  for the chemical oxygen demand of the to-be-tested liquid in the liquid storage space R 11 . In addition, the range of the wavelength of the light that allows travel through the first filter  581 , the second filter  582  and the third filter  583  could be changed according to the requirements of the detection item and the corresponding waveband of the used/selected light source. 
     In summary, the optical water-quality detection apparatus  500  provides one set of optical detection mechanisms which could simultaneously perform a variety of different detections, such as SS detection, COD detection, and copper ion concentration detection. 
     Referring to  FIG.  10   ,  FIG.  10    shows a schematic diagram of an experimental result of the optical water-quality detection apparatus according to the embodiment of the disclosure. The axis of abscissa represents the experiment time, and the axis of ordinate represents the signal sensed by the sensor. The curve C 1  represents the signal change of the optical water-quality detection apparatus of the embodiment of the disclosure within eight weeks of the experiment, and the curve C 2  represents the signal change of the optical water-quality detection apparatus that does not use the biofilm-inhibited light source within eight weeks of the experiment. According to the experimental results, the signal (which is sensed by the sensor), after the optical water-quality detection apparatus (using the biofilm-inhibited light source of 12 mW) is actually tested for eight weeks (the curve C 1 ), is reduced by only 1% to 2%. The signal, after the conventional optical water-quality detection apparatus that does not use the biofilm-inhibited light source is actually tested for eight weeks (the curve C 2 ), is reduced by up to 36.5%, wherein the signal presents instability in the 7th to 8th weeks (as shown in dashed frame of  FIG.  10   ), and it indicates that the sensed data is inaccurate. According to the experimental results, compared with the conventional optical water-quality detection apparatus that does not use the biofilm-inhibited light source, the optical water-quality detection apparatus of the disclosed embodiment could prolong the service life by 18 times. 
     In summary, the optical water-quality detection apparatus of the embodiment of the disclosure provides at least one detection optical path which could perform at least one characteristic/property detection of the to-be-tested liquid. In an embodiment, the optical water-quality detection apparatus includes the biofilm-inhibited light source and the detection light source, wherein the beam of the detection light emitted by the detection light source completely overlaps the beam of the inhibition light emitted by the biofilm-inhibited light source, accordingly it could simultaneously inhibit the biofilm for maintaining a proper accuracy of detection during detecting/inspecting the to-be-tested liquid. 
     It will be apparent to those skilled in the art that various modifications and variations could be made to the disclosed embodiments. It is intended that the specification and examples be considered as exemplary only, with a true scope of the disclosure being indicated by the following claims and their equivalents.