KR101293690B1 - Optical sensor for measuring water quality using rgb sensor - Google Patents

Abstract

PURPOSE: A light sensor device for measuring a water quality using an RGB sensor is provided to integrate light emitting diodes, the RGB sensor, and a light source filter into a sensor holder and to detachably insert the sensor holder into a sensor casing, thereby miniaturizing and lightening the sensor device at low costs. CONSTITUTION: A light sensor device (10) for measuring a water quality using an RGB sensor (11) includes light emitting diodes (9), a light source filter (12), a fluorescent film (8), a substrate (7), a fluorescent filter (13), and a measurement device. The light emitting diodes are installed on the front end surface of a sensor holder (14) at a predetermined interval. The light source filter is installed between the outer periphery of a light collecting pipe (14a) and the inner periphery of a sensor casing (1) and controls the frequencies of lights emitted by the light emitting diodes. The fluorescent filter emits the fluorescence of a specific frequency by reacting with the lights projected via the light source filter. The fluorescent film is coated on the substrate, and the substrate is installed inside a front cap. The fluorescent filter is installed inside the front end portion of the light collecting pipe and controls the frequencies of the fluorescence emitted by the fluorescent film. The measurement device is composed of the RGB sensor. The RGB sensor is arranged on the center of the sensor holder and inserted inside the sensor casing. The RGB sensor directly detects the colors of the light projected via the fluorescent filter, thereby measuring dissolved oxygen or pH.

Description

Optical sensor for measuring water quality using RGB sensor

The present invention relates to an optical sensor device for projecting light of a specific wavelength from a LED light source to a fluorescent film and then measuring a water quality standard such as dissolved oxygen or pH based on the fluorescence emitted from the fluorescent film. Instead of a camera, an RGB sensor is applied as a fluorescence measuring means, and a sensor holder in which an LED, an RGB sensor and an optical filter are integrated at an optimal position is inserted into a sensor casing, and a substrate coated with a fluorescent film on the front cap of the sensor casing. The present invention relates to an optical sensor device for measuring water quality using an AlgiBi sensor, which provides an inexpensive, compact and lightweight optical sensor device.

In general, dissolved oxygen (DO) or pH as an indicator of the water quality of coastal waters, rivers or lakes, etc., and the typical method of measuring the dissolved oxygen is Clark cell (galvanic or polar) The diaphragm method by graphic cell) is mainly used, and the method of measuring pH is mainly the method of immersing the electrode as an electrochemical sensor in water, and the electrode is often used for the measurement of dissolved oxygen.

While the above-mentioned diaphragm method has an advantage of excellent accuracy and reproducibility of measured values, the diaphragm cleaning problem, periodic replacement of the membrane and electrolyte, contamination of the membrane, periodic maintenance of the calibration, etc. There were many disadvantages in terms of the method, and the method using the electrode had the disadvantage that foreign substances such as algae or moss were easily attached while the electrode was in contact with water, and the electrode was frequently corroded, making it difficult to accurately measure the electrode. The hassle and cost burden of having to replace also caused.

As described above, it is possible to solve the disadvantages of the conventional diaphragm method or electrode method. When the light of a specific wavelength is projected onto the fluorescent material, the fluorescence generated from the fluorescent material is in contact with oxygen molecules or hydrogen ions. The measurement method using the point that generates the fluorescence wavelength in a specific area has been devised. When measuring dissolved oxygen or pH using the principle of fluorescence, the disadvantages of the conventional diaphragm method or electrode method can be solved at once. .

In other words, fluorescence refers to light emitted by an electronic transition or such a luminescence phenomenon when a material in an excited state (high energy state) returns to a ground state (low energy state). When a stimulus such as light is applied to a substance, the fluorescent substance is excited in the ground state, and the excited state is unstable, and if energy is not applied from the outside, it tries to return to the ground state by emitting light of the same wavelength absorbed. If oxygen molecules or hydrogen ions reduce the amount of fluorescence, the amount of oxygen molecules or hydrogen ions, ie dissolved oxygen and pH in water, can be measured by measuring the amount of fluorescence reduced.

As described above, an optical sensor device for measuring water quality using the principle of fluorescence includes an LED (light emitting diode) serving as a light source, a light source filter controlling a wavelength of light emitted from the LED, and light projected through the light source filter. A fluorescence film that emits fluorescence of a specific wavelength in response to the fluorescence, a fluorescence filter that controls the wavelength of fluorescence emitted from the fluorescence film, and a light measured through the fluorescence filter to measure dissolved oxygen or pH. Including an instrument, the measurement instrument is typically a digital camera such as a CCD camera or a DSLR camera.

However, the conventional optical sensor for water quality measurement not only significantly increases the price of the optical sensor device by using an expensive digital camera as a fluorescence measuring device, but also increases the overall volume and weight of the optical sensor device unnecessarily. Since it is difficult to integrate the sensor mechanism inside the small casing by appropriately disposing the LED and the optical filter based on the digital camera, only the LED and the optical filter are used as the sensor tip. Most of them are installed outside the sensor tip.

Therefore, the existing optical sensor device using a digital camera cannot measure dissolved oxygen or pH continuously while completely submerged in water, and can only measure dissolved oxygen or pH by immersing only the tip of the sensor in water. As a result, whenever there was a need for water quality measurement, the measuring equipment was transported to the measuring place to measure dissolved oxygen or pH, as well as the built-in dissolved oxygen in the tubular or aquaculture tank. By periodically measuring the pH, there was an inadequate problem to use for maintaining water quality and managing fish.

In particular, digital cameras are not devices that directly measure the wavelength (color) of light, but when light enters a microlens, the photodiode absorbs photons and emits charges, while charged coupled device (CCD) devices emit light. It stores the charged charge (voltage) and then amplifies and adjusts it to convert it into 8bit digital signal.So, it converts light into voltage and converts it into 8bit digital signal. In the process of implementation, sharpness of the color may be lowered.

In other words, a Bayer interpolation method in which an image processor embedded in a digital camera estimates the remaining values of the pixels based on signals of adjacent pixels without directly calculating RGB (Red, Green, Blue) values for every pixel. Since this is applied, the sharpness required to distinguish colors can be lowered in this interpolation process because of the characteristics of the optical sensor device that measures the values of dissolved oxygen and pH based on the specific color of fluorescence. There may be situations where accuracy and reliability cannot be guaranteed.

Republic of Korea Patent Registration 10-0860545 (Notification Date: September 26, 2008) Republic of Korea Patent Publication No. 10-2010-0137944 (published: December 31, 2010)

The present invention has been made to solve the above-mentioned conventional problems, while applying an RGB sensor instead of a conventional digital camera as a measuring means of the fluorescence emitted from the fluorescent film, while the filter mechanism and fluorescence of the light source emitted from the LED A filter device for fluorescence emitted from the film is reasonably disposed on the sensor holder along with the LED and RGB sensors, and the sensor holder is inserted into the sensor casing, and a substrate coated with a fluorescent film is disposed on the front cap of the sensor casing. The technical problem is to provide an inexpensive, compact and lightweight optical sensor device in which all means for measuring dissolved oxygen or pH are integrated inside the sensor casing.

In addition, the present invention minimizes the distortion that may occur during interpolation by applying an RGB sensor that directly measures the color (wavelength) of the light, so that the measured values of dissolved oxygen and pH measured from the optical sensor device are also very high. Accuracy and reliability, and the sensor holder including the LED, RGB sensor and optical filter can be easily separated from the sensor casing to make the repair or replacement of the sensor mechanism very easy. Another technical problem is to provide an optical sensor device that can be installed inside a water tank for a long time and optimized for periodically measuring dissolved oxygen or pH in water.

The present invention as a means for solving the above technical problem, the LED as a light source, a light source filter for controlling the wavelength of light emitted from the LED, and reacts with the light projected through the light source filter fluorescence of a specific wavelength A fluorescent film that emits light, a substrate of a transparent or translucent material coated with the fluorescent film, a fluorescent filter that controls the wavelength of the fluorescent light emitted from the fluorescent film, and a light emitted through the fluorescent filter to sense dissolved oxygen or In the optical sensor device for measuring the water quality comprising a measuring device for measuring the pH, the measuring device is an RGB sensor for measuring the dissolved oxygen or pH by directly detecting the color of the light projected through the fluorescent filter, The RGB sensor is inserted into and installed inside the sensor casing in a state of being disposed in the center of the sensor holder, and the front and rear ends of the sensor casing are front. The cap and the rear cap are assembled and installed with the sealing ring interposed therebetween, and a substrate coated with a fluorescent film is installed inside the front cap, and the light projected through the fluorescent filter at the front end side of the sensor holder is an RGB sensor. Inducing condensing pipes are installed, and the LED is installed in plurality at regular intervals on the front end surface of the sensor holder corresponding to the outer periphery of the condensing pipe, the fluorescent filter is installed inside the front end of the condensing pipe, the light source filter Is installed between the outer periphery of the condensing pipe and the inner periphery of the sensor casing (1), and a cable terminal is connected to the sensor holder, while a cable connected with the cable terminal extends through the sensor casing or the rear cap to the outside. It is characterized by being installed.

In addition, a battery storage unit for mounting a battery is provided at the side of the sensor holder, a controller for transmitting a signal generated from the RGB sensor and controlling the connection between the battery and the LED is installed in the center of the sensor holder, the sensor holder It is provided with a wiring structure for connecting the battery and the LED via a controller, the cable terminal is characterized in that the connection is installed with the controller, between the RGB sensor and the controller converts the analog signal output from the RGB sensor into a digital signal It is characterized in that the additional AD converter is provided.

More specifically, when the optical sensor device is used for measuring dissolved oxygen in the water, the LED is a blue light LED, the light source filter is a short pass filter passing only a wavelength of 470nm or less, the fluorescent filter Is a long pass filter passing only a wavelength of 530nm or more, the substrate is a transparent plate made of a polyester material having a thickness of 0.1 ~ 1mm, the fluorescent film is coated with a fluorescent dye for oxygen detection 0.1 to 2㎛ thickness The fluorescent film is a mixture of platinum octaethyl porphyrin, an oxygen detecting fluorescent dye, coumarin, an auxiliary dye, and polystyrene, a binder, in a weight ratio of 1: 1: 4, and the chloroform, which is a solvent, is 1:10 to After mixing at a weight ratio of 20, the solution is applied to a substrate with a thickness of 100 to 150 μm, characterized in that it is formed in a manner to volatilize the solvent component.

On the other hand, when the optical sensor device is used for measuring the pH of the water, the LED is an ultraviolet LED, the light source filter is a band pass filter passing only 405nm wavelength, the fluorescent filter is a wavelength of 455nm or more Being a long pass filter to pass through, the substrate is a transparent plate made of a polyester material having a thickness of 0.1 ~ 1mm, the fluorescent film is characterized in that the fluorescent dye for hydrogen ion detection is coated on the substrate with a thickness of 10 ~ 20㎛ The fluorescent film is mixed with a weight ratio of 1.5: 1.5: 10 of 8-hydroxy-1,3,6-pyrenetrisulfonic acid which is a fluorescent dye for detecting hydrogen ions, coumarin which is an auxiliary dye, and a polyurethane hydrogel as a binder. This is mixed with a solvent in which the ethanol and water are mixed at a volume ratio of 9: 1 at a weight ratio of 1: 5 to 10, and then the solution is applied to a substrate with a thickness of 100 to 150 µm to volatilize the solvent component.It characterized in that formed in the equation.

According to the present invention as described above, while applying the RGB sensor in place of the existing digital camera, all means for measuring dissolved oxygen or pH, that is, the LED and RGB sensor and the optical filter are integrated in the sensor holder, and the watertight ( By removably inserting into the inside of the sensor casing is a water treatment, there is an effect to provide a low-cost ultra-compact, light weight optical sensor device compared to the existing products.

In addition, by applying an RGB sensor that directly measures the color of the light (wavelength) without interpolation process and by optimizing the material of the optical filter and the fluorescent film to the RGB sensor, the dissolved oxygen and pH measured from the optical sensor device is very It has the effect of having a high level of accuracy and reliability, and provides an effect that the sensor holder can be easily separated from the sensor casing to perform the repair or replacement of the sensor mechanism very easily.

In particular, it is possible to periodically measure the dissolved oxygen or pH in the water for a long period of time by installing the optical sensor device inside the tubular tank or aquaculture tank, thereby keeping the water quality of the tank constant and safely keeping the fish safe. It has a very useful effect such as providing economic and reasonable water quality management means optimized for management purpose.

1 is an external perspective view of an optical sensor device according to the present invention.
Fig. 2 is a plan sectional view of Fig. 1; Fig.
3 is a side cross-sectional view of FIG.
4 is a sectional view taken along the line AA in Fig.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

As illustrated in FIGS. 1 to 4, the optical sensor device 10 for measuring water quality according to the present invention includes a light source for controlling a wavelength of light emitted from the LED 9 and the LED 9 as a light source. A filter 12, a fluorescent film 8 that emits fluorescence of a specific wavelength in response to the light projected through the light source filter 12, and a substrate of transparent or translucent material coated with the fluorescent film 8 ( 7), a fluorescence filter 13 for controlling the wavelength of fluorescence emitted from the fluorescence film 8, and a measuring instrument for detecting dissolved oxygen or pH by sensing light projected through the fluorescence filter 13 It is made, including.

A component corresponding to the first aspect of the present invention is a measuring mechanism for detecting dissolved oxygen or pH by detecting light projected through a fluorescence filter 13, and using an RGB sensor 11 instead of a conventional digital camera. As applied, the RGB sensor 11 is an electronic component that directly detects a color (intensity or wavelength) of light and generates a specific analog signal for each color.

The RGB sensor 11 defines a specific color by red, green, and blue, which are three primary colors of light. The RGB sensor 11 is generally applied to a television or a video system to obtain red, green, and blue colors. As it is signaled and transmitted, it is possible to reproduce color images based on the signal from a television set or a monitor. Recently, it is used as a part of a smartphone or a digital camera to adjust the brightness or sharpness of a screen. In addition to being widely used, it is also used to determine the plating or dyeing by measuring the color in the plating or dyeing process.

As the RGB sensor 11 itself can directly detect the color of light and transmit it as a specific analog signal, it can be sufficiently applied to the use of measuring dissolved oxygen or pH by detecting a simple color called fluorescence. Based on this perspective, the optical sensor device 10 is constructed by using the RGB sensor 11 without applying expensive components such as a CCD camera or a DSLR camera that realizes the image projected by the microlens as a digital image of various colors. will be.

In addition to the application of the RGB sensor 11 as described above, by optimizing the arrangement of the LED 9, the light source filter 12 and the fluorescent filter 13, it is required to manufacture the optical sensor device 10 as a very small, lightweight product For this purpose, a sensor mechanism comprising an RGB sensor 11, an LED 9, a light source filter 12, and a fluorescent filter 13 is integrated on a sensor holder 14, while the sensor holder is integrated. (14) is inserted into the cylindrical sensor casing (1) in a removable manner.

In the drawing, the RGB sensor 11 is mounted in the installation hole in the center of the sensor holder 14, and the light projected through the fluorescent filter 13 is guided to the RGB sensor 11 in the center of the tip side of the sensor holder 14. The condensing pipe 14a is formed to protrude, and the LEDs 9 are installed in plural at regular intervals on the front end surface of the sensor holder 14 corresponding to the outer periphery of the condensing pipe 14a. 13 is provided inside the tip of the condensing pipe 14a, and the light source filter 12 is provided between the outer periphery of the condensing pipe 14a and the inner periphery of the sensor casing 1.

When the sensor holder 14 is configured in the above manner, the RGB sensor 11 and the LED 9 can be safely protected by the light source filter 12, the fluorescent filter 13, and the condensing pipe 14a. Of course, the light source emitted from the LED 9 and the fluorescence induced by the RGB sensor 11 can be prevented from interfering with each other by the condensing pipe 14a, and the LED 9 and the RGB sensor 11 It is possible to provide a very simple and compact sensor unit by wiring an electric wiring or a circuit necessary for operation to the sensor holder 14.

Referring to FIG. 4, a total of four LEDs 9 are shown to be arranged at intervals of 90 degrees, but the number of installations of the LEDs 9 can be adjusted within a range of at least two to eight, Each LED 9 is preferably inclined toward the fluorescent film 8 at an angle of about 45 degrees. For this purpose, as shown in FIGS. 2 and 3, the front end surface of the sensor holder 14 is a condensing pipe. It is formed in the inclined surface inclined concavely toward 14a side.

In addition, the light source filter 12 may be a short-pass filter that passes only a wavelength below a specific wavelength band or a band-pass filter that passes only a specific wavelength band. A long-pass filter for passing only wavelengths above a specific wavelength band is generally used, and the optical filter corresponds to a known technique widely used in the field of optical sensors using the LEDs (13).

In addition, the front cap 2 and the rear cap 3 are assembled to the front end and the rear end of the sensor casing 1 by screwing, while the front cap 2 for the watertight treatment of the sensor casing 1. ) And a sealing ring (4) is applied to the assembly portion of the rear cap (3), and the substrate (7) coated with the fluorescent film (8) is installed inside the front cap (2), but the substrate (7) The watertight treatment is also made at the portion connected to the front cap (2).

By applying the prefabricated front cap 2 and the rear cap 3 to the front and rear ends of the sensor casing 1 as described above, the sensor holder 14 is easily separated from the sensor casing 1 so that the sensor Repair or replacement of the instrument can be carried out very easily, and for this purpose, the sensor holder 14 is composed of a cylindrical body in close contact with the inner circumferential surface of the sensor casing 1 and is inserted into the sensor casing 1 by fitting. It is desirable to install.

The sensor casing 1, the sensor holder 14, and the front cap 2 and the rear cap 3 are preferably made of a plastic material, but if necessary, the sensor casing 1, the front cap 2, and the rear cap are required. Cap 3 may be applied to a corrosion-resistant metal material or a metal material made of corrosion-resistant plating, the substrate 7 is preferably fixed to the inner peripheral surface of the front cap 2 by an adhesive method, the light source filter 12 And the fluorescence filter 13 are preferably installed on the basis of the condensing pipe 14a.

In addition, a cable 6 including a signal transmission line for transmitting a signal of the RGB sensor 11 to the outside and a power supply line for supplying power to the LED 9 from an unshown power source is provided in the sensor casing 1. Or through the rear cap 3 to be connected to the sensor holder 14, and the cable 6 is connected to an external computer terminal or a portable control panel and the like, while the RGB is connected via the sensor holder 14. It is connected with the sensor 11 and the LED 9, respectively.

Therefore, the dissolved oxygen or pH value measured by the RGB sensor 11 is displayed in the form of a numerical value or a graphic through a monitor provided to an external computer terminal or a portable control panel, and the lighting time of the LED 9 and the basis thereof. The measurement time of dissolved oxygen or pH is controlled by an external computer terminal or a portable control panel as an input means.

1 and 3, the cable 6 is inserted into the sensor casing 1 through the cable port 5 provided in the sensor casing 1, while the sensor is connected by the cable terminal 17. It is connected to the holder 14, the waterproof port (5a) is also installed in the cable port 5 to block the inflow of sea water or fresh water.

The reason why the cable 6 is penetrated to the body side of the sensor casing 1 as described above is that the front cap 2 and the rear cap 3 are screwed with the sensor casing 1 for repair or replacement of the sensor mechanism. Since the cable 6 is installed so as to penetrate the rear cap 3, the cable 6 is installed in the penetrating portion of the cable 6 under conditions that ensure the connection between the sensor holder 14 and the cable terminal 17. This is because it is difficult to apply watertight treatment.

Of course, instead of the cable terminal 17 of the type shown in the drawings, a pin-type plug is connected to the cable 6, and the snap ring is applied to the sensor holder 14 by applying a pipe socket. By using the coupling mechanism of the type), the cable 6 may pass through the rear cap 3, but the connection state between the cable 6 and the sensor holder 14 is more reliably ensured and the optical sensor device ( In order to lower the unit cost of 10), it may be advantageous to apply the scheme shown in the drawings.

On the other hand, when considering the aspect to periodically measure the dissolved oxygen or pH in the water for a long time by installing the optical sensor device 10 of the present invention in the interior of the tubular aquarium or aquaculture tank, the sensor holder ( By providing the battery compartment 14b for mounting the battery 18 to 14, it is even more preferable to enable the mounting of the battery 18 to the sensor holder 14, the battery 18 being pin Various types of batteries such as lithium batteries or button batteries may be applied.

In addition, a controller 16 is additionally installed at the center of the sensor holder 14 to transmit signals generated from the RGB sensor 11 and to control connection between the battery 18 and the LED 9. 6) is connected to the controller 16 and the cable terminal 17 using only a signal transmission line, the sensor holder 14 is connected to the battery 18 and the LED (9) via the controller 16 To be provided.

As a representative example of the wiring structure, the (+) wire or the (-) wire for the LED 9 is connected to the (+) or (-) pole of the battery 18, and the (-) for the LED 9 The battery 18 and the LED 9 are connected to the controller 18 in a state where a wire or a positive wire is connected to the negative or positive electrode of the battery 18 via the controller 16. In addition to providing a switch circuit necessary for the connection of the control circuit, a program for controlling the connection cycle and the connection time of the battery 18 and the LED 9 by the switch circuit is incorporated.

Even more preferably, an AD converter 15 for converting an analog signal output from the RGB sensor 11 into a digital signal is further provided between the RGB sensor 11 and the controller 16. The optical sensor device 10 according to the present invention is to directly control the oxygen supply device such that the water quality management means that can maintain the water quality of the seawater or fresh water stored in the tank constant, AD controller 15 in the controller 16 It is advantageous to further provide a function for amplifying the digital signal generated through the transmission to the outside.

When using the optical sensor device 10 of the present invention configured as described above for the measurement of dissolved oxygen, the LED (9) is applied to a blue light LED (Blue LED), the blue light LED to measure the dissolved oxygen It is preferable to use a high-brightness LED 9 having a peak wavelength (λ-peak) of 445 nm, a power of 340 mW, and a current of 700 mA.

In addition, the substrate 7 is a transparent plate made of a polyester (Polyester) material having a thickness of 0.1 ~ 1mm, the fluorescent film 8 is a fluorescent dye for oxygen detection of the substrate 7 to a thickness of 0.1 ~ 2㎛ The fluorescent film 8 is preferably formed on the outer surface of the substrate 7, that is, on the surface in contact with sea water or fresh water, and a representative example of the oxygen detecting fluorescent dye is ruthenium or platinum. Octaethyl porphyrin (Platinum Octaethly Porphyrin: PtOEP) and the like.

As described above, since red (orange to red) fluorescence is expressed from the fluorescent film 8 when the dissolved oxygen is measured using the blue light LED 9, the light source filter 12 has a wavelength of blue light or less, that is, 470 nm or less. The fluorescent filter 13 is another light source that can be measured by the RGB sensor 11 while being installed as a short-pass filter through which only the light passes. Only a wavelength of 530 nm or more is prevented so that green light adjacent to the fluorescence is not transmitted. Long-pass filter is used.

In addition, the reason for the thickness of the substrate 7 to be 0.1 to 1 mm is to ensure sufficient permeability of light irradiated to the fluorescent film 8 through the substrate 7 and at the same time, It is because it is an optimum range which can satisfy the intensity | strength, and polyester used as the raw material of the board | substrate 7 becomes a material excellent in corrosion resistance with respect to seawater, without causing chemical reaction with the component which comprises the fluorescent film 8.

In addition, the fluorescent film 8 is formed by mixing a fluorescent dye for oxygen detection with a binder and a solvent to coat the surface of the substrate 7. For this purpose, the fluorescent dye is processed into a fine powder form. By mixing with a binder and a solvent, the thickness of the fluorescent film 8 to be in the range of 0.1 ~ 2㎛ to prevent waste of the fluorescent dye and to ensure the expression of fluorescence and the service life of the fluorescent film (8) It is preferable in terms of.

In an embodiment of the present invention, the platinum octaethyl porphyrin (PtOEP), coumarin (cooumarin) and the polystyrene (binder) of the binder are 1: 1: It is mixed at a weight ratio of 4 (wt%), and it is mixed with a solvent of chloroform (Chloroform) at a weight ratio of 1:10 to 20 (wt%), and then the solution is 100-150 μm thick. ) To form a solvent component by volatilization.

The platinum octaethyl porphyrin (PtOEP) is an excellent oxygen measurement fluorescent dye that expresses 650 nm of red light at 0% dissolved oxygen conditions, and the coumarin provides fluorescence of PtOEP by providing additional energy required for fluorescence of PtOEP. Although the coumarin dye itself generates a green fluorescence of 480 nm level under blue light conditions, the green fluorescence is caused by an RGB sensor (long pass filter) 13 that passes only wavelengths of 530 nm or more. 11) Since it does not penetrate the side, it does not interfere with the measurement of dissolved oxygen.

In addition, polystyrene as a binder and chloroform as a solvent are optimal materials for firmly attaching the dye onto the substrate 7 without causing a chemical reaction with PtOEP and coumarin dyes, and 1: 1 with PtOEP, coumarin, and binder. The reason for mixing at a weight ratio of 4: 4 and mixing it at a weight ratio of 1:10 to 20 with chloroform as a solvent is optimal for uniformly distributing PtOEP and coumarin and stably applying it to the substrate 7. It is because it is a ratio, and when the solution is apply | coated to the board | substrate 7 in thickness of 100-150 micrometers, and a solvent component is volatilized, the fluorescent film 8 which has a thickness of 0.1-2 micrometers can be obtained.

On the other hand, when using the optical sensor device 10 of the present invention for the measurement of pH, the LED 9 is applied to the ultraviolet LED (UV LED) bar, it is also used to use the ultraviolet LED for the measurement of pH It is already known in the field of optical sensors, and it is preferable to use a high brightness LED 9 having a peak wavelength (λ-peak) of 405 nm, a power of 460 mW, and a current of 700 mA.

As described above, the substrate 7 is a transparent plate made of a polyester material having a thickness of 0.1 to 1 mm, and the fluorescent film 8 has a thickness of 10 to 20 μm with a fluorescent dye for detecting hydrogen ions. ), And a representative example of a fluorescent dye for detecting hydrogen ions is 8-hydroxy-1,3,6-pyrenetrisulfonic acid (HPTS). The reason for limiting the thickness of the fluorescent film 8 for pH measurement and the manner of forming the fluorescent film 8 are applied in the same manner as described above on the basis of the dissolved oxygen measurement.

Since the green-based fluorescence is expressed from the fluorescent film 8 when measuring the pH using the ultraviolet LED 9 as described above, the light source filter 12 is a band-pass filter (Band-pass only passing the wavelength of 405nm in the ultraviolet region) In the filter installed state, the fluorescent filter 13 is another light source that can be measured by the RGB sensor 11, and a long pass filter that passes only a wavelength of 455 nm or more so as not to transmit blue light in a region adjacent to the fluorescence is used. .

In the present invention, as an optimal embodiment of the fluorescent film 8 for pH measurement, the 8-hydroxy-1,3,6-pyrenetrisulfonic acid (HPTS) and auxiliary The dye coumarin and the binder polyurethane hydrogel are mixed in a weight ratio (wt%) of 1.5: 1.5: 10, and the solvent is mixed with ethanol and water in a volume ratio of 9: 1. After mixing at a weight ratio (wt%) of 1: 5 to 10, the solution is applied to the substrate 7 to a thickness of 100 to 150 µm to form a solvent component by volatilization.

The 8-hydroxy-1,3,6-pyrenetrisulfonic acid (HPTS) is an excellent pH measurement fluorescent dye that expresses 555 nm green light at pH 10 conditions, and the coumarin is fluorescence of HPTS as described above. By providing additional energy needed for fluorescence, HPTS is a medium to further promote fluorescence, and coumarin itself generates 420nm of blue fluorescence under ultraviolet conditions, but this blue fluorescence is applied to a long pass filter that passes only wavelengths of 455nm or more. Because it is not transmitted to the RGB sensor 11 side, it does not cause a problem in the measurement of pH.

In addition, the solvent mixed with the polyurethane hydrogel and ethanol and water as the binder is an optimal material that can firmly adhere the dye on the substrate (7) without causing a chemical reaction with HPTS and coumarin dyes, The reason for mixing coumarin and binder in a weight ratio of 1.5: 1.5: 10, and mixing them in a solvent in which ethanol and water are mixed in a volume ratio of 9: 1 in a weight ratio of 1: 5 to 10 is because of HPTS and coumarin This is because it is an optimum ratio that can uniformly distribute the substrate 7 to the substrate 7, and when the solution is applied to the substrate 7 to a thickness of 100 to 150 μm, the solvent component is volatilized. A fluorescent film 8 having a thickness of can be obtained.

Finally, when a hydrogel sheet containing carbon powder is coated on the surfaces of the dissolved oxygen measuring fluorescent film 8 and the pH measuring fluorescent film 8 to a thickness of about 10 μm, the fluorescent film ( 8) can induce about 20% of the fluorescence emitted in the water to the RGB sensor 11 side, but the application of the carbon coating layer does not significantly affect the actual measured value by the RGB sensor 11 as an experiment. It was confirmed that the application of the carbon coating layer is a matter that can be selected as needed.

1: Sensor casing 2: Front cap 3: Rear cap
4: sealing ring 5: cable port 5a: waterproof packing
6 cable 7 substrate 8 fluorescent film
9: LED 10: light sensor device 11: RGB sensor
12 light source filter 13 fluorescent filter 14 sensor holder
14a: condensing pipe 14b: battery housing 15: AD converter
16 controller 17 cable terminal 18 battery

Claims (7)

LED 9 which becomes a light source, the light source filter 12 which controls the wavelength of the light radiate | emitted from the LED 9, and reacts with the light projected through the light source filter 12, and emits fluorescence of a specific wavelength A fluorescent film (8), a transparent or semi-transparent substrate (7) coated with the fluorescent film (8), a fluorescent filter (13) for controlling the wavelength of fluorescence emitted from the fluorescent film (8), In the optical sensor device for measuring the water quality comprising a measuring mechanism for detecting the dissolved oxygen or pH by detecting the light projected through the fluorescent filter (13),
The measuring device is an RGB sensor 11 that directly detects the color of light projected through the fluorescence filter 13 and measures dissolved oxygen or pH, and the RGB sensor 11 is located at the center of the sensor holder 14. Inserted into the interior of the sensor casing (1) is disposed,
The front cap 2 and the rear cap 3 of the sensor casing 1 are assembled to the front cap 2 and the rear cap 3 with the sealing ring 4 interposed therebetween, and a fluorescent film inside the front cap 2. 8) coated substrate 7 is installed,
A condensing pipe 14a for guiding the light projected through the fluorescent filter 13 to the RGB sensor 11 is installed at the central portion of the front end side of the sensor holder 14, and the LED 9 is the condensing pipe 14a. Are installed in a plurality at regular intervals on the front end surface of the sensor holder 14 corresponding to the outer peripheral edge of the,
The fluorescent filter 13 is installed inside the tip of the condensing pipe 14a, and the light source filter 12 is installed between the outer periphery of the condensing pipe 14a and the inner periphery of the sensor casing 1,
A cable terminal 17 is connected to and installed in the sensor holder 14, while a cable 6 connected to the cable terminal 17 extends through the sensor casing 1 or the rear cap 3 to the outside. Optical sensor device for measuring the water quality using the Algibi sensor, characterized in that. The method of claim 1, wherein the optical sensor device is used for measuring the dissolved oxygen in water,
The LED 9 is a blue LED, the light source filter 12 is a short-pass filter that passes only a wavelength of 470nm or less, the fluorescent filter 13 is 530nm or more It becomes a long-pass filter that passes only wavelengths,
The substrate 7 is a transparent plate of a polyester material having a thickness of 0.1 ~ 1mm, the fluorescent film 8 is characterized in that the fluorescent dye for oxygen detection is coated on the substrate 7 with a thickness of 0.1 ~ 2㎛ Optical sensor device for water quality measurement using the Algibi sensor. The method of claim 2, wherein the fluorescent film 8 comprises platinum octaethyl porphyrin (PtOEP), which is a fluorescent dye for oxygen detection, coumarin, which is an auxiliary dye, and polystyrene, which is a binder, in a 1: 1: It is mixed at a weight ratio of 4 (wt%), and it is mixed with a solvent of chloroform (Chloroform) at a weight ratio of 1:10 to 20 (wt%), and then the solution is 100-150 μm thick. ) Optical sensor device for measuring the water quality using an Algibi sensor, characterized in that formed in a way to apply a volatilized solvent component. The method of claim 1, wherein the optical sensor device is used for measuring the pH in water,
The LED 9 becomes an ultraviolet LED (UV LED), the light source filter 12 becomes a band-pass filter that passes only a wavelength of 405 nm, and the fluorescent filter 13 only has a wavelength of 455 nm or more. It will be a long-pass filter
The substrate 7 is a transparent plate made of a polyester material having a thickness of 0.1 ~ 1mm, the fluorescent film 8 is a fluorescent dye for detecting hydrogen ions is coated on the substrate 7 to a thickness of 10 ~ 20㎛ Optical sensor device for measuring the water quality using the Algibi sensor. The method of claim 4, wherein the fluorescent film 8 is 8-hydroxy-1,3,6-pyrenetrisulfonic acid (HPTS), which is a fluorescent dye for detecting hydrogen ions. Coumarin and auxiliary dyes were mixed in a binder (polyurethane hydrogel) in a weight ratio of 1.5: 1.5: 10 (wt%), and ethanol and water were mixed in a volume ratio of 9: 1. Algi ratio, characterized in that formed by mixing the solvent in a weight ratio (wt%) of 1: 5 to 10, and then applying the solution to the substrate 7 to a thickness of 100 ~ 150㎛ Optical sensor device for measuring water quality using sensors. 6. The battery holder 14b according to claim 1, wherein a side surface of the sensor holder 14 is provided with a battery storage portion 14b for mounting the battery 18. A controller 16 is installed for transmitting signals generated from the RGB sensor 11 and controlling the connection between the battery 18 and the LED 9.
The sensor holder 14 is provided with a wiring structure for connecting the battery 18 and the LED 9 via the controller 16, the cable terminal 17 is connected to the controller 16, characterized in that the installation Optical sensor device for water quality measurement using Algivy sensor. 7. An AD converter (15) is further provided between the RGB sensor (11) and the controller (16) to convert an analog signal output from the RGB sensor (11) into a digital signal. Optical sensor device for water quality measurement using Algivy sensor.

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