DE202010014885U1 - Evaluation circuit for an optical touch sensor - Google Patents
Evaluation circuit for an optical touch sensor Download PDFInfo
- Publication number
- DE202010014885U1 DE202010014885U1 DE202010014885U DE202010014885U DE202010014885U1 DE 202010014885 U1 DE202010014885 U1 DE 202010014885U1 DE 202010014885 U DE202010014885 U DE 202010014885U DE 202010014885 U DE202010014885 U DE 202010014885U DE 202010014885 U1 DE202010014885 U1 DE 202010014885U1
- Authority
- DE
- Germany
- Prior art keywords
- evaluation circuit
- touch sensor
- optical touch
- sensor according
- ambient light
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Images
Classifications
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
- H03K17/94—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the way in which the control signals are generated
- H03K17/96—Touch switches
- H03K17/962—Capacitive touch switches
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
- H03K17/94—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the way in which the control signals are generated
- H03K17/941—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the way in which the control signals are generated using an optical detector
Landscapes
- Electronic Switches (AREA)
Abstract
Auswerteschaltung für einen optischen Berührungssensor nach
Description
Die vorliegende Erfindung betrifft eine Auswerteschaltung für einen optischen Berührungssensor auf Grundlage einer Reflexlichtschranke. Die Auswerteschaltung ist dabei in der Lage Umgebungslichteinflüsse ohne zusätzliche Sensoren herauszufiltern. Hierfür wird lediglich der Fototransistor FT1 benötigt, der als Empfangseinheit der Reflexlichtschranke dient. Eine Stabilisierung des Arbeitspunktes des Fototransistors und die Kompensation des Umgebungslichtes erfolgt indirekt durch eine Abschwächung des Nutzsignals am Eingang der Verstärkerstufe. Hierdurch ist es möglich mit einem festen Verstärkungsfaktor des Operationsverstärkers zu arbeiten. Am Ausgang der Verstärkerstufe liegt ein Puls an, der direkt auf einen digitalen Eingang eines Mikrokontrollers geschaltet werden kann. Eine Auswertung über einen Analog- zu Digitalkonverter und eine aufwendige Auswertung des Signals im Mikrokontroller ist nicht erforderlich.The present invention relates to an evaluation circuit for an optical touch sensor based on a reflected light barrier. The evaluation circuit is able to filter out ambient light influences without additional sensors. For this purpose, only the phototransistor FT1 is needed, which serves as a receiving unit of the reflected light barrier. A stabilization of the operating point of the phototransistor and the compensation of the ambient light takes place indirectly by a weakening of the useful signal at the input of the amplifier stage. This makes it possible to work with a fixed amplification factor of the operational amplifier. At the output of the amplifier stage is a pulse, which can be switched directly to a digital input of a microcontroller. An evaluation via an analog to digital converter and a complex evaluation of the signal in the microcontroller is not required.
Beschreibungdescription
Stand der TechnikState of the art
Aus
Der Nachteil der Schaltungen liegt in der Verwendung des zweiten Sensors. Zusätzlich muss das Nutzsignals aus den Analogsignalen aufwendig errechnet werden.The disadvantage of the circuits lies in the use of the second sensor. In addition, the useful signal from the analog signals must be calculated consuming.
Aufgabenstellungtask
Die Aufgabe der Erfindung ist es eine Empfangseinheit zu schaffen, die die Nachteile des Stands der Technik aufhebt und insbesondere eine einfache und kostengünstige Schaltung und eine einfache Auswertung über einen Mikrokontroller ermöglicht. Eine vorteilhafte Ausgestaltung wird mit den in den Schutzansprüchen aufgeführten Merkmalen gelöst.The object of the invention is to provide a receiving unit which overcomes the disadvantages of the prior art and in particular enables a simple and inexpensive circuit and a simple evaluation via a microcontroller. An advantageous embodiment is achieved with the features listed in the protection claims.
Ausführungsbeispielembodiment
Die Ausführung der Schaltung wird in
Die vorgeschlagene Schaltung nach
ZITATE ENTHALTEN IN DER BESCHREIBUNG QUOTES INCLUDE IN THE DESCRIPTION
Diese Liste der vom Anmelder aufgeführten Dokumente wurde automatisiert erzeugt und ist ausschließlich zur besseren Information des Lesers aufgenommen. Die Liste ist nicht Bestandteil der deutschen Patent- bzw. Gebrauchsmusteranmeldung. Das DPMA übernimmt keinerlei Haftung für etwaige Fehler oder Auslassungen.This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.
Zitierte PatentliteraturCited patent literature
- WO 2010/047807 A1 [0002] WO 2010/047807 A1 [0002]
Claims (8)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE202010014885U DE202010014885U1 (en) | 2010-10-26 | 2010-10-26 | Evaluation circuit for an optical touch sensor |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE202010014885U DE202010014885U1 (en) | 2010-10-26 | 2010-10-26 | Evaluation circuit for an optical touch sensor |
Publications (1)
Publication Number | Publication Date |
---|---|
DE202010014885U1 true DE202010014885U1 (en) | 2011-02-17 |
Family
ID=43603874
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
DE202010014885U Expired - Lifetime DE202010014885U1 (en) | 2010-10-26 | 2010-10-26 | Evaluation circuit for an optical touch sensor |
Country Status (1)
Country | Link |
---|---|
DE (1) | DE202010014885U1 (en) |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2010047807A1 (en) | 2008-10-22 | 2010-04-29 | Tom Chang | Light detection circuit for ambient light and proximity sensor |
-
2010
- 2010-10-26 DE DE202010014885U patent/DE202010014885U1/en not_active Expired - Lifetime
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2010047807A1 (en) | 2008-10-22 | 2010-04-29 | Tom Chang | Light detection circuit for ambient light and proximity sensor |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
DE102004047786A1 (en) | Correction of the effect of pulses in a gas flow, especially the intake flow into a motor vehicle multi-cylinder combustion engine, by multiple filtering of input signals prior to adding in an adder circuit | |
DE102007042315B3 (en) | Measuring circuit with switched capacitor for measuring the capacitance of an input capacitor | |
DE102005020901A1 (en) | Method and system for diagnosing mechanical, electromechanical or fluidic components | |
DE2918420A1 (en) | IC engine knock detector circuit for capacitive sensor - compares filtered and unfiltered demodulator outputs and requires no tuning | |
DE102014119240A1 (en) | Flow measuring device according to the differential pressure measuring principle for measuring a flow of a medium | |
DE102006005563A1 (en) | Capacitance type sensor for detecting a physical quantity | |
DE102005020900B3 (en) | Mechanical, electromechanical, and fluidic components diagnosing method for valve, involves subsampling measuring signal, and generating error message signal if intensity of subsampled measuring signal exceeds defined threshold value | |
DE202010014885U1 (en) | Evaluation circuit for an optical touch sensor | |
DE102010050096A1 (en) | Evaluation circuit for optical touch sensor, performs stabilization of operating point of phototransistor and ambient light compensation, and attenuates signal behind high-pass filter capacitor based on low-frequency voltage at resistor | |
CH617771A5 (en) | ||
DE102005034859A1 (en) | Measuring arrangement for measuring the inductance and the resistance value of an inductive sensor | |
EP0460407A2 (en) | Sensor circuit | |
EP2501036B1 (en) | Circuit configuration for evaluating photoelectric measurements | |
WO2003098230A1 (en) | Method and assembly for detecting the motion of an element | |
EP2545650A1 (en) | Method for evaluating an analog signal | |
DE4446535B4 (en) | Circuit arrangement for amplitude measurement | |
CH618792A5 (en) | ||
DE102018109915A1 (en) | EMC robust microelectronic integrated measuring circuit for capacitance values of unknown capacity | |
DE102017120015A1 (en) | Circuit arrangement for line break detection for continuously scanning measuring systems | |
DE69415374T2 (en) | Device for indicating the level of a liquid in a tank, in particular for motor vehicles, with a damping circuit | |
DE4220761C2 (en) | Automotive sensor arrangement | |
DE10242406A1 (en) | Direct current motor rotational velocity measurement method in which the voltage to the motor is supplied across a field effect transistor and the resultant voltage drop signal across the FET used to generate a motor speed signal | |
DE10303495B4 (en) | Method for offset determination of angle sensor signals | |
DE102021211498A1 (en) | Circuit arrangement for processing an analog ultrasonic signal detected by an ultrasonic converter and for converting the analog ultrasonic signal into a digital ultrasonic signal, as well as an ultrasonic sensor and a vehicle with such a circuit arrangement | |
EP0559087B1 (en) | Digital period measuring circuit |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
R207 | Utility model specification |
Effective date: 20110324 |
|
R156 | Lapse of ip right after 3 years |
Effective date: 20140501 |