Refraction Patent

Background of the invention

 

Field of the invention:

 

The Present invention relates to a refractive measuring device to determine properties of liquids.

 

Description of the Prior Art:

 

There already do exist refractive measuring devices that can determine properties of liquids.  However, all of these systems use complicated optical arrays and cavities to determine the properties, which make them expensive and quite difficult to operate.  The prior products use a point source light, usually a LASER light source, with one light receiver, pointed at an angle through what is being measured.  The light then refracts and the receiving device, usually a CCD, determines the shift in the light path.  See diagram 1.

Description of Diagram 1:

 

This system uses sophisticated components, often together with lenses (not shown).  This makes for an expensive product.

1 – Point light source, usually a LASER.

2 – Light receiving device, usually a CCD

3 – Liquid being measured, either flowing or stationary

4 – Extension of original light beam (un-refracted) from light source (1), to show difference in comparison to beam number 5

5 – Refracted Light beam.

 

Summary of the Invention:

 

Purely Scientific Principle:

 

The principle of this invention is based upon Snell’s law: n1 sin1 = n2 sin2. In this equation n1 is the refractive index of the surrounding medium and n2 is the refractive index of the substance being measured.   And 1 is the angle at which the electromagnetic wave (Referenced as em or electromagnetic wave or light through out document) touches a substance with respect to the normal and 2 is the angle at which it goes in to the liquid with respect to the normal.

 

Definitions:

 

Normal – The line perpendicular to the surface at which the angles are measured in reference to.

Index of Refraction – determined by dividing the speed of light in the medium by the speed of 

light in a vacuum ( C0 / v )

 

Scientific Principle in Relation to Product:

 

The following invention is a reliable method for determining the purity of liquid, contaminants of liquid or type of liquid.  The liquid may be flowing at any speed, or / and it may be stationary. 

 

The system uses one or more light emitting devices opposite one or more light detecting devices are used as in figure 2.  Figure 2 shows an example involving 2 emitters and 2 detectors, although they can be arranged in other ways also, they do not have be in equal quantities.  A slit or pillar is put in front of both light emitting devices to break the electromagnetic wave down into two separate ones.  This is done because the light in the middle of the emitter will fall at an angle of 180 degrees on to the curved or straight liquid holder or directly on to the liquid, which will result in no refraction.  However the remaining light will refract and give us our reading. 

 

In the following figure 1, this basic refraction principle, on which the product is based can be seen.

 

Description of Figure 1

 

            * - Lines 3, 5 and 9 represent electromagnetic waves.

            1 – Angle of incidence of incoming electromagnetic wave 3 from the surrounding medium into liquid.

            2 – Normal for lines 3 and 5. 

            3 – Incoming electromagnetic wave

            4 – Center line

            5 – Refracted incoming electromagnetic wave, following from line 3.

            6 – Angle of refraction of incoming electromagnetic wave 5 from the surrounding medium into liquid.

            7 – Angle of incidence of incoming electromagnetic wave (now outgoing) from liquid to surrounding medium.

            8 – Normal for lines 5 and 9.

            9 – Refracted outgoing electromagnetic wave, following from line 5.

            10 – Angle of refraction of outgoing electromagnetic wave 9 from the liquid to the surrounding medium.

 

Description of Figure 2:

 

1 – Light detecting device receiving light from light emitting device 4.

2 – Light detecting device receiving light from light emitting device 3

3 – Light emitting device directing light to light receiving device 2

4 – Light emitting device directing light to light receiving device 1

5 – Liquid being measured.  The liquid may be flowing or contained in a container of any shape.

6 – Light emitted by light emitting devices before reaching masks (9).

7 – Light emitted by light emitting devices after passing through masks (9).

8 – Light emitted by light emitting devices after passing through masks (9).

9 – Mask or pillars put in front of light emitting devices to change the way light reaches detectors.  It can be in any shape or size.

10 – Mask placed in front of light detecting device.  It can be any shape or size.

11 – Mask placed in front of light detecting device.  It can be any shape or size.

 

Remember also that when a beam of light strikes a curved piece of a non-opaque substance, the thru light will go to a common focal point.  The focal point is determined simply by the diameter of the curvature and the index of refraction of the substance.  See figure 3.  A circle is shown for ease of reference.

 

Focal Length = n D / [4 (n-1)]

Description of Figure 3:

1 – Diameter of curved non-opaque surface

2 – Incoming light

3 – Focal Length

 

The curved piece of material in this invention is the tube through which the liquid flows.  Therefore the focal length will remain constant unless liquid flows through.  This change of focal length is what the circuit requires.

 

As with the light emitting devices, the light receiving devices also have masks or posts in front.  As can be seen in figure 2, the photo-transistors can be placed in different locations, one is further back than the other with respect to their incident LED’s.  This means that each photo-transistor will receive different amounts of light depending on the liquid or purity of the liquid being measured. 

 

In reference to figure 2: When pure liquid “a” is being analyzed, 100% of the incident light from the light emitting device 3 goes to light receiving device 2, and 50% of the incident light from the light emitting device 4 goes to light receiving device 1.  Then, when impurities are in the liquid, the index of refraction changes slightly, this then changes the focal points of the incident beams on the light receiving devices.  This results in more or less light reaching the light receiving devices.  And when there is X% difference in the readings of the light receiving devices, the circuit switches, which causes an exterior signal or other warning device to turn on., thus warning the customer of the problem.

 

This X% is determined by the customer, and represents the threshold of the liquid from acceptable to unacceptable.  The circuit is calibrated to the desired liquid the customer wants with the tolerances of purity he desires, or other specs altogether.  This may seem tedious at first, but for an OEM customer, this will only have to be done once, since in the circuit, the light emitting devices and light receiving devices can be moved along rails and then glued into place for ease of testing and setting up.

This principle may be accomplished in several ways.  A, B, C and D in figure 4.

Description of Figure 4:

A – The light source and receiver are exactly opposite each other on different sides of the liquid or liquid holder. (Picture 1)

A1 – Light emitting source (in straight line with light receiving device).

A2 – Light receiving device (in straight line with light emitting device).

A3 – Direction of liquid flow, any direction or speed

A4 – Liquid, or liquid in a holder.

 

B – The light source and receiver are opposite each other, with a vertical angle (6) in between them.

B1 – Light emitting source (at a vertical angle with respect to light receiving device).

B2 – Light receiving device (at a vertical angle with respect to light emitting source). 

B3 – Direction of liquid flow, any direction or speed.

B4 – Liquid, or liquid in a holder.

B6 – Angle in between emitter and receiver.

 

C – The device which measures the liquid (4) has a thread on both sides (Picture 1) for a system of flowing or stationary liquid to be attached.  At the top of the device is a non-opaque extrusion (5), and below this is a system to whirl the liquid up to the extrusion so it can be measured in the same fashion as A and B.

C1 – Light emitting source (in straight line with light receiving device)

C2 – Light receiving device (in straight line with light emitting device)

C3 – Direction of liquid flow, any direction or speed

C4 – Liquid, or liquid in a holder.

C5 – Extrusion for liquid to go into for it to be measured.

 

D – The device which measures the liquid (4) has a thread on both sides (Picture 2) for a system of flowing or stationary liquid to be attached.  At the top of the device is a non-opaque extrusion (5), and below this is a system to whirl the liquid up to the extrusion so it can be measured in the same fashion as A and B.

D1 – Light emitting source (at a vertical angle with respect to light receiving device).

D2 – Light receiving device (at a vertical angle with respect to light emitting source).

D3 – Direction of liquid flow, any direction or speed

D4 – Liquid, or liquid in a holder.

D5 – Extrusion for liquid to go into for it to be measured.

D6 – Angle in between emitter and receiver.

 

Claims:

1 – A liquid property measuring device which uses 2 or more light sources to obtain a complementary reading over a preferably round flow of liquid.

 

2 – A mask is placed in front of each light source, creating the desired light “shape”, preferably eliminating the light in the middle, for it will not refract. 

 

3 – The light receiving devices are placed in different positions with respect to their incident light emitters.  One is further back than the other.  This allows for different amounts of light to reach each light receiver depending on the liquid being measured.

 

4 – By creating 4 or more light beams, the device allows for maximum deviation, while using minimum power.  Also it allows the use of low power consumption which in turn allows the device to be certified for use in hazardous areas.

 

5 – The design allows the creation of a portable liquid detector.  This device can be slid over a non-opaque pipe with liquid in it.