WO2018041564A1

WO2018041564A1 - Optical sensor device and method for analyzing an analyte

Info

Publication number: WO2018041564A1
Application number: PCT/EP2017/070175
Authority: WO
Inventors: Roland Seitz; Juergen Kurle; Paul Koop
Original assignee: Robert Bosch Gmbh
Priority date: 2016-08-29
Filing date: 2017-08-09
Publication date: 2018-03-08
Also published as: DE102016216209A1

Abstract

The invention relates to an optical sensor device (1) for analyzing an analyte, comprising a transmission device (11) for transmitting a light beam (L), a detection device (12) for detecting the light beam (L), a housing (13) which has an optical window (1311) and which encloses the transmission device (11) and the detection device (12), and a reflection device (14) for reflecting the light beam (L), said reflection device being arranged on the housing (13) such that a test volume (V) for receiving the analyte is formed between the reflection device (14) and the optical window (1311). The transmission device (11) is designed to transmit the light beam (L) through the optical window (1311) and the test volume (V) and onto the reflection device (14). The detection device (12) is designed to detect the light beam (L) which is reflected on the reflection device (14) after the light beam passes through the test volume (V) and the optical window (1311) and to output an analysis signal.

Description

description

Title:

Optical sensor device and method for analyzing an analyte

The present invention relates to an optical sensor device for

Analyzing an analyte and a method of using an optical sensor device to analyze an analyte.

State of the art

Spectroscopic analysis by means of optical measuring systems makes it possible to determine individual components in fluids, gases or transparent solids. A common technique is ATR (Attenuated Total Reflection) - infrared spectroscopy. Here, light is transmitted under total reflection by a crystal or a light guide, whereby the light intensity weakens, since light can quantum mechanically tunnel out of the crystal or light guide and interact with the surrounding analyte. By measuring the attenuation of the light intensity components of the analyte can be determined. A method for measuring the CO 2 content of fluids by means of such an ATR sensor is known, for example, from EP 2 607 887 A2.

Since more and more sensors are used under very fluctuating conditions in most cases, there is a need for

cost-effective, compact and robust optical sensor devices which simultaneously have high precision.

Disclosure of the invention

The invention provides an optical sensor device for analyzing an analyte having the features of patent claim 1 and a method for Use of an optical sensor device for analyzing an analyte with the features of patent claim 9.

According to a first aspect, the invention therefore relates to an optical

Sensor device for analyzing an analyte, with a

Transmitting device, which is designed to emit a light beam, and a detection device, which is adapted to detect the light beam. The sensor device further comprises a housing which comprises an optical window and the emitting device and the

Includes or einhaust detection device. A reflection device for reflecting the light beam is arranged on the housing such that a test volume or a cavity for receiving the analyte is formed between the reflection device and the optical window. The emitting device is adapted to the light beam through the optical window and the

Send test volume to the reflection device. The

Detection device detects the reflected light beam at the reflecting device after passing through the test volume and the optical

Window. The detection device outputs based on the received

Light beam from an analysis signal.

The analyte can be, for example, a fluid, a gas or an at least partially transparent solid.

The housing may preferably be a TO (transistor outline) housing, so that the optical sensor device can be produced cost-efficiently and is compatible with other components due to the uniform standardization.

The reflection device may preferably have a reflecting or reflecting surface, which faces the emitting device. The reflection device may, in particular, have a curved surface, which is designed to deflect or form the light beam appropriately.

The detection device can analyze the analysis signal in particular based on a frequency, a frequency shift, an intensity, a change in intensity, a phase shift and / or an expansion of the received

Determine the light beam.

According to a further aspect, the invention relates to a method for

Use of an optical sensor device for analyzing an analyte. For this purpose, in a first method step, the analyte is introduced into the test volume between the reflection device and the optical window. Furthermore, the light beam is emitted by means of the emitting device and the light beam reflected by the reflecting device passes through the light beam

Detection device received and an analysis signal by the

Detection device issued. The analyte is analyzed by the analysis signal.

Preferred embodiments are the subject of the respective subclaims. Advantages of the invention

By the emitting device and the detection device are arranged in a common housing, is a compact structure of

Device possible. The optical sensor device is very robust against external environmental influences and at the same time has a high precision.

According to a preferred embodiment of the optical sensor device, the housing has a carrier device and an encapsulation. The emitting device and the detection device are here on the

Carrier device arranged. On the carrier device further electronic evaluation devices can be arranged. For example, the carrier device may have a printed circuit board on which the

Aussendeeinrichtung and the detection device are arranged or fixed.

According to a further preferred embodiment of the optical

Sensor device are the emitting device and / or the

Detection device contacted by means of pins, which is determined by the

Carrier extending through out of the housing. The Sensor device may be suitable in particular for push-through mounting and can thereby be easily combined with other modules.

According to a preferred embodiment of the optical sensor device, the emitting device is adapted to a light beam with a

Wavelength between 3 and 50 microns. The

Transmitting device is preferably designed to emit a light beam in the mid-infrared range. Particularly preferably sends the

Emitting device a light beam with a wavelength between 3 and 8 micrometers. Radiation in the mid-infrared range is also well reflected if the reflection device is easily contaminated due to age, so that the high precision of the optical sensor device is maintained in this case as well.

According to a preferred development of the optical sensor device, at least one optical filter device is arranged between the emission device and the optical window and / or between the optical window and the reflection device. For example, certain

Wavelength ranges are filtered to more accurately determine certain components in the analyte.

According to a preferred refinement, the optical sensor device has an evaluation device which is designed to use an optical signal based on the analysis signal output by the detection device

Transmission property and / or to determine a composition of the analyte. Thus, certain components of the analyte, such as a CO 2 content, of the analyte can be detected.

According to a development of the optical sensor device, the latter has a sensor device which is designed to detect a change in pressure and / or a change in the chemical composition in the interior of the housing. Furthermore, the optical sensor device has a control device which is designed to deactivate the emitting device and / or to issue a warning signal if the sensor device has a

Pressure change and / or a change in the chemical composition in the Inside the housing detected. The optical sensor device is thereby also for use with a temperature-sensitive or inflammatory

Analytes suitable. If, due to damage or leakage of the housing, the analyte enters the interior of the housing, it is deactivated by deactivating the

Dispensing device prevents that due to the operating temperature of the emitting device, which may be more than 300 °, the analyte is ignited. A leak in the housing can thus be reliably detected and the safety of the optical sensor device can be increased. The sensor device may, for example, have a pressure sensor which detects a pressure change when the pressure deviates from a predetermined threshold value.

According to a preferred development of the optical sensor device, the reflection device has a protective coating made of a light-transmitting material. Here, the part under the protective coating is the

Reflecting device designed reflective or reflective and is protected by the protective coating from dirt or damage. The reflection device can also be a protective coating of a

have reflective material which reflects the emitted light beam.

According to a preferred development of the method, analyzing the analyte comprises determining a transmission property and / or a composition of the analyte.

Brief description of the drawings

1 shows a schematic cross-sectional view of an optical

Sensor device according to an embodiment of the invention;

Fig. 2 is a schematic oblique view of the optical shown in Fig. 1

Sensor device; Fig. 3 is a schematic oblique view of that shown in Fig. 1

Sensor device, wherein the capsule is not illustrated;

4 is a schematic cross-sectional view of that shown in FIG

optical sensor device, wherein the optical window and the reflection means are not illustrated;

Fig. 5 is a schematic plan view of the optical shown in Fig. 1

Sensor device;

Fig. 6 is a schematic cross-sectional detail view of an optical

Sensor device according to another embodiment;

7 shows a schematic oblique view of an optical sensor device with an ATR crystal arranged on the housing;

8 shows a schematic oblique view of an optical sensor device with a light guide arranged on the housing;

9 shows a schematic oblique view of an optical sensor device with a medium-conducting channel passing through the housing;

FIG. 10 is a schematic cross-sectional view of the optical sensor device illustrated in FIG. 9; FIG. and

11 is a flowchart of a method for analyzing a

Analytes by means of an optical sensor device.

In all figures, the same or functionally identical elements and devices are provided with the same reference numerals. The numbering of

Procedural steps are for clarity and generally should not imply a particular chronological order. In particular, several method steps can be carried out simultaneously. Various

Embodiments may be combined as desired, if appropriate. Description of the embodiments

In Fig. 1 is a schematic cross-sectional view of an optical

Sensor device 1 illustrated according to an embodiment of the invention. A transmission device 11 and a detection device 12 are on a carrier device 132, preferably a silicon substrate or a

PCB, arranged. The emitting device 11 is adapted to emit a light beam L, wherein a wavelength of the light beam L

preferably in the mid-infrared range. The emitting device 11 may comprise an LED, a micromechanical emitter, a light bulb and / or a laser.

On the emitting device 11 is in the beam path an optical

Filter device 17 is arranged, which is adapted to filter the emitted light beam L. In particular, the optical filter device 17 can filter out a specific wavelength range.

The carrier device 132, together with an encapsulation 131, forms a housing 13, which encloses the emitting device 11 and the detection device 12. Preferably, the housing is hermetically sealed, so that the emitting device 11 and the detection device 12 are not in fluidic contact with the environment. The encapsulation 131 comprises a capsule 1312, which is preferably made of metal, and has a first opening 191 through which the light beam L emitted by the emitting device 11 can be emitted. The capsule 1312 further has a second opening 192, through which light can pass to the detection device 12. The openings 19, consisting of the first opening 191 and the second opening 192, are hermetically sealed by an optical window 1311, which is preferably made of silicon or of a plastic and is arranged on the capsule 1312. The optical window 1311 and the capsule 1312 form the encapsulation 131 of the housing 131. On the capsule 1312, a reflection device 14 is arranged such that a test volume V for receiving the analyte is formed between the reflection device 14 and the optical window 1311. For this purpose, as shown in the oblique view in FIG. 2, the capsule 1312 has a bulge, in which the optical window 1311 is arranged, so that the

Reflection device 14 is spaced from the optical window 1311. The test volume may be open to one or two sides. In particular, an analyte in the form of a gas or a fluid can flow into the test volume V.

The reflecting device 14 has a mirrored side facing the optical window 1311, which is designed to be similar to that of the

Transmitting device 11 emitted light beam L to reflect.

For this purpose, the reflection device 14 preferably has a protective coating of a reflective or translucent material. The light beam L reflected at the reflection device 14 may fall onto the detection device 12 after passing through the test volume V and the analyte located in the test volume V as well as through the optical window 1311. The detection device 12 is designed to detect the light beam L and to output a corresponding analysis signal. Thus, the detection device 12 can detect and output a frequency spectrum, an intensity or a phase shift of the light beam L. The

Detection device 12 may comprise at least one of a thermopile, a pyrodetector or a photodetector.

Furthermore, a sensor device 16 is arranged on the carrier device 132, which comprises a pressure sensor, which can detect a pressure change in the interior of the housing 13. The sensor device 16 can preferably be further configured to detect a change in the chemical composition in the interior of the housing 13.

The emitting device 11 is connected via a connecting wire 18 to a first pin 151 which extends through the carrier device 132 out of the housing 13 out. Similarly, the detection device 12 is connected to a second pin 152 and the sensor device 16 is connected to a third pin 153 connected. The pins 15, comprising the first pin 151, the second pin 152 and the third pin 153, are connected to a control device 21 and an evaluation device 20.

The evaluation device 20 is designed to be based on the of the

Detection device 12 output an optical signal analysis signal

Transmission property and / or to determine a composition of the analyte. The evaluation device 20 may in particular a Wellenlängenbzw. Evaluate the frequency spectrum of the received light beam L and thereby analyze the analyte.

The control device 21 is designed to deactivate the emitting device 11 and / or to issue a warning signal if the sensor device 16 detects a pressure change and / or a change in the chemical composition in the interior of the housing 13.

The optical sensor device 1 can be connected via the pins 15 to printed circuit boards or other electronic devices.

FIG. 3 illustrates the optical sensor device 1 in an oblique view, the capsule 1312 having been omitted for better illustration. FIG. 4 shows a schematic cross-sectional view of the optical sensor device 1, wherein the optical window 1311 and the reflection device 14 have been omitted for the sake of clarity. As can be seen from FIG. 4, the capsule 1312 has a projection 13121 which is designed in such a way that transversely incident external light radiation can not reach the openings 19 and thus a transverse influence is reduced. It is prevented that light from outside the sensor device 1 is detected by the detection device 12.

FIG. 5 shows a plan view of the optical sensor device 1.

FIG. 6 shows a schematic oblique view of a detail of an optical sensor device according to a further embodiment of the invention.

Accordingly, the emitting device 11, the detection device 12 and the Sensor device 16 is not arranged directly on the carrier device 132, but on a printed circuit board 60 which is arranged on the carrier device 132. The remaining structure of the optical sensor device may correspond to the embodiment described above.

FIG. 7 shows an optical sensor device 2. Instead of the

Reflector 14 here is an ATR crystal 200 in a recess of the capsule 1312. The emitting device 11 is adapted to emit a light beam in the direction of the ATR crystal 200 and the detection device 12 is adapted to reflect the reflected in the ATR crystal 200th Receive light beam L and output a corresponding analysis signal. In this case, the detection device 12 measures a weakening of the intensity of the light beam due to an interaction of the light beam with an analyte L which is located outside the ATR crystal 200.

FIG. 8 shows a further optical sensor device 3. Instead of the ATR crystal 200, a light guide 303 is arranged on the capsule 1312 via a light coupling device 301 and a light coupling device 302. The

The emitting device 11 is designed to couple a light beam L into the light guide 303 via the light coupling device 301. Of the

Light beam L is passed through the optical waveguide 303 under total reflection, with a weakening of the intensity due to an interaction of the

Light beam L on the tunneling effect with an analyte outside the

Optical fiber 303 occurs. The light beam L is detected by the detection device 12 and this is based on a reduction in the intensity of the

Light beam L from an analysis signal.

FIG. 9 shows a schematic oblique view of a further optical system

Sensor device 4. FIG. 10 illustrates a schematic cross-sectional view of the optical sensor device 4. A transparent Mediumleitkanal 401 passes through the capsule 1312, wherein the Mediumleitkanal 401 is designed for receiving or passing an analyte. through

Sealing mechanisms 402, 403, entry and exit areas of the Mediumleitkanals 401 are closed in the capsule 1312, so that the capsule 1312, which is arranged on the support means 132, a hermetically sealed including sealed room. A emitting device 11 arranged on the carrier device 132 is designed to emit light through the medium guide channel 401. Furthermore, a detection device 12 is arranged on the carrier device 132, which is designed to detect the light beam L after passing through the medium guide channel 401 with the analyte and to output an analysis signal. The detection device 12 is connected via a connecting wire 405 with a pin 404 and thereby contactable. It can also be provided a plurality of Mediumleitkanälen, in particular for conducting different analytes.

FIG. 11 shows a flow chart for explaining a method for

Use of an optical sensor device 1 for analyzing an analyte. The method can preferably be carried out with a sensor device 1 illustrated in FIGS. 1 to 6.

In a first method step S1, the analyte is introduced into the test volume V between the reflection device 14 and the optical window 1311. The analyte can be introduced by placing the optical sensor device 1 in a fluid or in a gas and thereby allowing the analyte to enter the test volume V.

In a second method step S2, a light beam L by means of

Emitting device 11 sent out. The light beam L, after passing through the optical filter 17, the optical window 1311 and the test volume V with the analyte, is reflected by the reflection means 14 and, after re-passing through the test volume V with the analyte and through the optical window 1311, the detection means 12 detected. The

Detection device 12 outputs an analysis signal based on the received light beam L.

In a further method step S4, the analyte is determined on the basis of

Analysis signal analyzed. In particular, a transmission property of the analyte and / or a composition of the analyte can be determined.

Claims

claims

An optical sensor device (1) for analyzing an analyte, comprising emitting means (11) for emitting a light beam (L); a detection device (12) for detecting the light beam (L); a housing (13) having an optical window (1311) and including the emitting means (11) and the detecting means (12); and a reflection means (14) for reflecting the light beam (L) which is arranged on the housing (13) such that between the

Reflection device (14) and the optical window (1311)

Test volume (V) is designed to receive the analyte; wherein the emitting device (11) is adapted to the light beam (L) through the optical window (1311) and the test volume (V) on the

To send reflection means (14); and wherein the detection device (12) is adapted to the at the

Reflection means (14) reflected light beam (L) after passing through the test volume (V) and the optical window (1311) to detect and output an analysis signal.

2. Optical sensor device (1) according to claim 1, wherein the housing (13) has a carrier device (132) and an encapsulation (131), wherein the emitting device (11) and the detection device (12) on the

Support means (132) are arranged.

3. An optical sensor device (1) according to claim 2, wherein the

Transmitter device (11) and / or the detection device (12) can be contacted by means of pins (15), which can be contacted by the carrier device (132). through out of the housing (13) extend out.

Optical sensor device (1) according to one of the preceding claims, wherein the emitting device (11) is adapted to emit a light beam (L) having a wavelength between 3 and 50 micrometers.

Optical sensor device (1) according to one of the preceding claims, wherein between the emitting device (11) and the optical window (1311) and / or between the optical window (1311) and the

Reflection device (14) at least one optical filter device (17) is arranged.

Optical sensor device (1) according to one of the preceding claims, having an evaluation device (20) which is designed to use the analysis signal output by the detection device (12) for an optical signal

Transmission property and / or to determine a composition of the analyte.

An optical sensor device (1) according to any one of the preceding claims, comprising sensor means (16) adapted to detect a change in pressure and / or a change in the chemical composition inside the housing (13); and a control device (21), which is designed, the

To deactivate emitting device (11) and / or output a warning signal if the sensor device (16) detects a pressure change and / or a change in the chemical composition in the interior of the housing (13).

Optical sensor device (1) according to one of the preceding claims, wherein the reflection device (14) has a protective coating of a light-transmissive and / or reflective material.

A method of using an optical sensor device (1) according to any one of claims 1 to 8 for analyzing an analyte, comprising the steps of: Introducing (Sl) the analyte into the test volume (V) between the

Reflection means (14) and the optical window (1311);

Emitting (S2) a light beam (L) by means of the emitting device (11);

Receiving (S3) the reflected at the reflection means (14)

Light beam (L) and outputting an analysis signal through the

Detection device (12); and

Analyze (S4) the analyte based on the analysis signal.

10. The method of claim 9, wherein analyzing the analyte comprises determining an optical transmission property and / or a composition of the analyte.