Infrared sensor module and forehead thermometer

An infrared sensor module and a forehead thermometer are provided. The infrared sensor module includes a light guide structure and an infrared sensor element. An annular hollow space is formed inside the light guide structure and passes therethrough. A first and second opening is formed on two opposite sides of the light guide structure, respectively. A diameter of the first opening is greater than a diameter of the second opening. The annular hollow space includes a matte and reflective area, the matte area has serration portions, and each of the serration portions extends from the first opening to the second opening and is arranged parallel to each other. The reflective area is formed between the second opening and the matte area. The infrared sensor element is disposed at the second opening. The forehead thermometer includes a casing, a circuit board, the infrared sensor module, and an operating switch.

FIELD OF THE DISCLOSURE

The present disclosure relates to an infrared sensor module and a forehead thermometer, and more particularly to an infrared sensor module and a forehead thermometer having a light guide structure.

BACKGROUND OF THE DISCLOSURE

Firstly, when an infrared forehead thermometer is used for measuring human body temperatures in conventional technology, the forehead thermometer is usually required to be placed at 1 to 3 cm (or even closer) from the center of a forehead to avoid measuring infrared energy around the center of the forehead. This is to accurately measure the temperature of a human body, since an infrared sensor element used in the infrared forehead thermometer generally measures at a viewing angle greater than 120 degrees. Therefore, when the infrared forehead thermometer is positioned too far away from the human body, not only does the infrared emitted from the center of the human forehead enter the infrared forehead thermometer, but lower or higher infrared energy other than the infrared emitted from the center of the human forehead can also enter the forehead thermometer and be received by the infrared sensor element. This results in distortion of temperature values measured by the forehead thermometer.

Moreover, when the infrared forehead thermometer is positioned too far away from the human forehead, even if the infrared radiation that is emitted from the center of the human forehead enters the forehead thermometer, a part of the energy may still be lost due to the distance between the infrared forehead thermometer and the human forehead. This causes the infrared sensor element to receive the infrared and convert it into a signal that is too weak to be distinguished from noise, which also results in distortion of the temperature values measured by the forehead thermometer.

Therefore, how to improve an optical structural design of the forehead thermometer to make the forehead temperature measuring viewing angle to be smaller and to have a longer measuring distance for filtering out unnecessary external light, as well as simultaneously focusing the infrared radiation to enlarge or at least maintain the infrared energy received by the infrared sensor element, so as to overcome the above-mentioned shortcomings, has become one of the important issues to be solved in this field.

SUMMARY OF THE DISCLOSURE

In response to the above-referenced technical inadequacies, the present disclosure provides an infrared sensor module and a forehead thermometer.

In one aspect, the present disclosure provides an infrared sensor module. The infrared sensor module includes a light guide structure and an infrared sensor element. An annular hollow space is formed inside the light guide structure, the annular hollow space passes through the light guide structure, and a first opening and a second opening are formed on two opposite sides of the light guide structure, respectively. A diameter of the first opening is greater than a diameter of the second opening. The annular hollow space includes a matte area and a reflective area. The matte area has a plurality of serration portions, and each of the serration portions extends from the first opening to the second opening. The reflective area is formed between the second opening and the matte area. The infrared sensor element is disposed at the second opening.

In another aspect, the present disclosure provides a forehead thermometer. The forehead thermometer includes a casing, a circuit board, an infrared sensor module, an operating switch, and a display panel. The casing has an opening. The circuit board is disposed inside the casing. The infrared sensor module is disposed inside the casing and is electrically connected to the circuit board, and a first opening of the infrared sensor module is spatially communicated with the opening. The operating switch is disposed on the casing and is electrically connected to the circuit board. The operating switch is electrically connected to the infrared sensor module through the circuit board. The display panel is disposed on the casing and is electrically connected to the circuit board. The infrared sensor module includes a light guide structure and an infrared sensor element. An annular hollow space is formed inside the light guide structure, the annular hollow space passes through the light guide structure, and a first opening and a second opening are formed on two opposite sides of the light guide structure, respectively. A diameter of the first opening is greater than a diameter of the second opening. The annular hollow space includes a matte area and a reflective area. The matte area has a plurality of serration portions, and each of the serration portions extends from the first opening to the second opening. The reflective area is formed between the second opening and the matte area. The infrared sensor element is disposed at the second opening.

One of the beneficial effects of the present disclosure is that, in the infrared sensor module and the forehead thermometer provided herein, by virtue of “the infrared sensor module including a light guide structure and an infrared sensor element”, “an annular hollow space being formed inside the light guide structure and the annular hollow space passing through the light guide structure, and a first opening and a second opening being formed on two opposite sides of the light guide structure, respectively”, “a diameter of the first opening being greater than a diameter of the second opening”, “the annular hollow space including a matte area and a reflective area”, “the matte area having a plurality of serration portions, and each of the serration portions extending from the first opening to the second opening and being arranged parallel to each other”, “the reflective area being formed between the second opening and the matte area”, “the infrared sensor element being disposed at the second opening”, “the forehead thermometer including a casing, a circuit board, an infrared sensor module, an operating switch, and a display panel”, “a casing having an opening, and the first opening of the infrared sensor module being spatially communicated with the opening”, “the circuit board and the infrared sensor module being disposed inside the casing”, “the operating switch being disposed on the casing and electrically connected to the circuit board, and the operating switch being electrically connected to the infrared sensor module through the circuit board”, and “the display panel being disposed on the casing and electrically connected to the circuit board.”, the infrared sensor module and the forehead thermometer can filter out unnecessary external light at a longer measuring distance, as well as simultaneously enlarging or at least maintaining the infrared energy received by the infrared sensor element to improve the accuracy of the human body temperature that is measured.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

First Embodiment

References are made toFIG.1toFIG.4, in which an infrared sensor module is provided in a first embodiment of the present disclosure. The infrared sensor module includes a light guide structure1and an infrared sensor element2. An annular hollow space10is formed inside the light guide structure1. The annular hollow space10passes through the light guide structure1, and a first opening101and a second opening102are formed on two opposite sides of the light guide structure1, respectively. It should be noted that a diameter of the first opening101is greater than a diameter of the second opening102.

The light guide structure1is further described herein. References are made toFIG.1andFIG.4, in which the annular hollow space10includes a matte area103and a reflective area104. A length L1of the matte area103is 1 to 3 times a length L2of the reflective area104, and an inner diameter of the matte area103is greater than or equal to an inner diameter of the reflective area104. The matte area103has a plurality of serration portions105that are arranged in a continuous manner. Each of the serration portions105extends from the first opening101to the second opening102, and furthermore, a tooth-like tip of each of the serration portions105extends from the first opening101to the second opening102, such that each of the serration portions105extends along an axis of the annular hollow space10. A surface of the serration portions105is rough and can be coated with a layer of black matte paint. The reflective area104is formed between the second opening102and the matte area103. A surface of the reflective area104is a parabolic mirror surface and is plated with a layer of metal such as nickel or gold that has high infrared reflectivity, such that the surface of the reflective area104can better reflect and focus the infrared.

The infrared sensor element2can be disposed at the second opening102. The infrared sensor element2can receive infrared that is emitted from the center of the human forehead, and then convert the infrared into a signal that can be displayed using temperature units. Therefore, when the infrared is emitted from the center of the human forehead and enters an infrared sensor module M through the first opening101, the infrared passes the matte area103and the reflective area104sequentially, before finally being received by the infrared sensor element2.

However, due to the infrared sensor module not being in direct contact with the human forehead, it is inevitable that light B (including infrared) present around the center of the forehead will also enter the infrared sensor module through the first opening101. In detail, since the infrared sensor module is aimed at the center of the human forehead for measuring temperatures, the infrared that is emitted from the center of the human forehead and the light B that is around the center of the forehead are two different light sources. The infrared being emitted from the center of the human forehead enters the infrared sensor module through the first opening101at a small angle, while the light B being around the center of the forehead enters the infrared sensor module through the first opening101at a large angle, as shown inFIG.1.

Reference is further made toFIG.1, showing the infrared (not shown in the figures) being emitted from the center of the human forehead and entering into the annular hollow space10in the light guide structure1. Since the infrared that is emitted from the center of the human forehead has a smaller incident angle, the infrared comes in contact with the matte area103, but does not come in contact with the reflective area104. The infrared is then reflected once or multiple times and focused by the surface of the reflective area104, and enters the infrared sensor element2. As mentioned above, since the reflective area104is a smooth mirror surface or a smooth surface that is plated with bright nickel, the infrared being emitted from the center of the human forehead will not lose energy when the infrared is reflected by the surface of the reflective area104. Therefore, the infrared sensor element2can receive and convert an entirety of infrared that is emitted from the center of the human forehead to stronger signals, such that signals are not so weak as to be covered by the noise.

On the other hand, the light B around the center of the forehead enters the annular hollow space10in the light guide structure1at a large angle, so that it will reach the serration portions105of the matte area103first. As mentioned above, structures of the serration portions105extend along the axis of the annular hollow space10, and the surface of the serration portions105is rough or coated with a layer of black matte paint; therefore, when external light B reaches the serration portions105, the external light B will reflect continuously between the surfaces of the serration portions105. The energy of the external light B that is continuously reflected between the surfaces of the serration portions105will constantly experience loss and have energy escape, and will not be received by the infrared sensor element2. Furthermore, since the length L1of the matte area103is 1 to 3 times the length L2of the reflective area104, ensuring that the length of the reflection path of the light B around the center of the forehead in the matte area103is long enough, a probability of the light B around the center of the forehead being lost is increased.

In this present embodiment, the inner diameter of the matte area103is gradually tapered inward (toward the reflective area104) from the first opening101. That is, the tooth-like tips of the serration portions105form a tapered structure. In addition, in this present embodiment, a surface profile of the reflective area104is a paraboloid and the infrared sensor element is located at a focus point of the paraboloid. In this way, the infrared that is emitted from the human body can be further concentrated through surface reflection of the reflective area104and be received by the infrared sensor element2, such that the signal strength of the converted temperature signal is further improved. In other words, in comparison with conventional technology, the light guide structure1provided in the present disclosure can reduce infrared energy outside of the center of the forehead at a longer measuring distance and increase the focus of the infrared energy at the center of the forehead.

Second Embodiment

References are made toFIGS.5to7, showing another embodiment of the light guide structure of the present disclosure. The surface characteristics of the matte area103and the reflective area104, and the usage of the matte area103and the reflective area104in the present embodiment are the same as those in the first embodiment, and will not be repeated herein. The main difference between the present embodiment and the first embodiment is that the tooth-like tips of the serration portions105form a cylindrical structure, and a surface profile of the reflective area104is an isosceles trapezoid.

Furthermore, in this embodiment, a light guide structure1includes a first light guide structure11and a second light guide structure12that are connected with each other. A matte area103is disposed inside the first light guide structure11, a first opening is formed on the first light guide structure11, a reflective area104is disposed inside the second light guide structure12, and a second opening is formed on the second light guide structure12. The first light guide structure11includes a third opening111, and the second light guide structure12includes a fourth opening121. The first light guide structure11and the second light guide structure12are connected with each other through the third opening111and the fourth opening121, respectively, and a diameter of the third opening111is greater than or equal to a diameter of the fourth opening121.

In other words, the light guide structure1in the first embodiment is an integrally formed element, while in the second embodiment, the light guide structure1is a combination of elements formed by connecting the first light guide structure11and the second light structure12together.

It is worth mentioning that although the surface profile of the reflective area104in the first embodiment is a paraboloid, and the surface profile of the reflective area104in the second embodiment is an isosceles trapezoid, the present disclosure is not limited thereto. In other embodiments, the surface profile of the reflective area104can also be an ellipse.

References are made toFIGS.1, and8to10, in which a forehead thermometer Z is provided in the present disclosure. The forehead thermometer Z includes a casing3, a circuit board4, an operating switch5, a display panel6and an infrared sensor module M of the present disclosure. The infrared sensor module M is disposed inside the casing3and is electrically connected to the circuit board4. The infrared sensor module M includes the light guide structure1and an infrared sensor element2.

The infrared sensor element2is electrically connected to the circuit board4. The light guide structure1has a connecting member13, and the connecting member13is disposed on an outer surface of the light guide structure1. The light guide structure1of the present disclosure is first connected to a fixing member14through the connecting member13, and then secured on the circuit board4by the fixing member14. It should be noted that the connecting member13can have other configurations and connection methods depending on different implementations. The above-mentioned example is only one of feasible embodiments, and is not intended to limit the present disclosure.

An annular hollow space10is formed inside the light guide structure1, the annular hollow space10passes through the light guide structure1, and a first opening101and a second opening102are formed on two opposite sides of the light guide structure1, respectively. A diameter of the first opening101is greater than a diameter of the second opening102. The annular hollow space10includes a matte area103and a reflective area104. The matte area103has a plurality of serration portions105that are arranged in a continuous manner.

Each of the serration portions105extends from the first opening101to the second opening102. The reflective area104is formed between the second opening102and the matte area103, and the infrared sensor element2is disposed at the second opening102.

When the infrared sensor module M is disposed inside the casing3, the first opening101is spatially communicated with an opening30. That is, the first opening101and the opening30are spatially communicated while overlapping with each other, so that infrared being emitted from the center of the human forehead or light B being around the center of the forehead can enter the infrared sensor module M through the opening30(or the first opening101) and can be received by the infrared sensor element2.

The operating switch5is disposed on the casing3and is electrically connected to the circuit board4. The operating switch5is electrically connected to the infrared sensor module M through the circuit board4. The display panel6is disposed on the casing3and is electrically connected to the circuit board4. A user activates and controls the infrared sensor module M through the operating switch5to perform infrared temperature measurement, and the temperature value that is measured is displayed on the display panel6for the user to view.

Beneficial Effects of the Embodiments

One of the beneficial effects of the present disclosure is that, in the infrared sensor module M and the forehead thermometer Z as provided, by virtue of “the infrared sensor module M including a light guide structure1and an infrared sensor element2”, “an annular hollow space10being formed inside the light guide structure1, the annular hollow space10passing through the light guide structure1, and a first opening101and a second opening102being formed on two opposite sides of the light guide structure1, respectively”, “a diameter of the first opening101being greater than a diameter of the second opening102”, “the annular hollow space10including a matte area103and a reflective area104”, “the matte area103having a plurality of serration portions105, and each of the serration portions105extending from the first opening101to the second opening102and being arranged parallel to each other”, “the reflective area104being formed between the second opening102and the matte area103”, “the infrared sensor element2being disposed at the second opening102”, “a forehead thermometer Z including a casing3, a circuit board4, an infrared sensor module M, and an operating switch5”, “the casing3having an opening30, and the first opening101of the infrared sensor module M being spatially communicated with the opening30”, “the circuit board4and the infrared sensor module M being disposed inside the casing3”, and “the operating switch5being disposed on the casing3and electrically connected to the circuit board4, and the operating switch5being electrically connected to the infrared sensor module M through the circuit board4”, the infrared sensor module M and the forehead thermometer Z can filter out unnecessary external light, as well as simultaneously enlarging or at least maintaining the infrared energy received by the infrared sensor element to improve the accuracy of the human body temperature that is measured.

Furthermore, since the external light B enters the infrared sensor module M of the present disclosure at a large angle, the infrared that is emitted from the center of the human forehead enters the infrared sensor module M of the present disclosure at a relatively small angle. Therefore, in the present disclosure, the matte area103in the light guide structure1is utilized to filter out the external light B at the large angle to improve the accuracy of the temperature that is measured. In addition, in the present disclosure, the reflective area104in the light guide structure1is utilized to reflect the infrared that is emitted from the center of the human forehead to enlarge or at least to maintain the infrared energy being emitted therefrom. In this way, the infrared that is emitted from the center of the human forehead does not lose much energy when being received by the infrared sensor element2, such that the converted temperature signal is not too weak. That is, in comparison with the conventional technology, the light guide structure1provided in the present disclosure can reduce infrared energy around the center of the forehead at a longer measuring distance and increase the focus of the infrared energy at the center of the forehead.