Tag: Biomedical measurements
-
What is the Function of a Phonocardiograph?
A phonocardiogram is a recording of the heart sounds and murmurs. The instrument used to make this recording is called the phonocardiograph. The recording of all the heart sounds during a cardiac cycle is termed to as phonocardiography. Phonocardiogram eliminates the subjective interpretation of the heart sounds and makes it possible to evaluate them with…
-
How Liquid Crystal Sensors are used in Biomedical Measurements
The principle of operation of liquid crystal sensors is based on the fact that liquid crystals change their state in such way that they modify passive scattering or absorption of light. As the crystal melt, the three-dimensional order becomes a two-dimensional or one dimensional order, layers or strands form that can be seen as a…
-
Key Factors to Consider in the Design and Operation of Electrocardiograph
There are various factors that must be considered in the design and application of the electrocardiograph. These key factors must be considered by the biomedical engineer as well as the electrocardiograph operator and the physician who interprets the recorded information. We discuss these factors as follows: Frequency distortion The electrocardiograph does not always meet the…
-
The Essential Requirements of Biopotential Amplifiers for Medical applications
Biopotential amplifiers are also termed to as Bioamplifiers. Bioelectric measurements are normally low-level voltages with high source impedances therefore signal amplification is essential part of biomedical measurement systems. The signal amplification is needed to boost or increase the strength of the input signal to match the requirements of recording/display systems. We have specialized amplifiers designed…
-
Biomedical Instrumentation Questions & Answers
Q1. What are the problems encountered in biomedical measurements? The problems encountered in biomedical measurements are: Q2. What are the key requirements for specifying biomedical instrumentation systems? They key specifications to consider when specifying biomedical instruments include: Q3. What are the diagnoses made from Electroencephalogram (EEG)? The brain cells are referred to as neurons. The…
-
The Functions of Signal Conditioners in Biomedical Measurement Systems
In a Biomedical measurement system, the electrodes pick up the bioelectrical potential whereas the transducer converts the physiological signal to be measured into a usable electrical output. The outputs from the Bioelectrodes/transducers are then converted into an electrical quantity that is suitable for operating a display or recording device with the help of a signal…
-
Why Patient Monitoring Instruments are Important in Medical Care
The main objective of patient monitoring is to have a quantitative assessment of the important physiological variables of the patient during critical periods of their biological functions. In medical diagnostic and research, it is necessary to know their actual value or trend of change. Medical monitoring instruments are used for measuring continuously or at regular…
-
Types of Bioelectrodes
Introduction Bioelectric events have to be picked up from the surface of the body before they can be put to the amplifier for subsequent record or display. This is done by use of electrodes. The potentials produced at different points are measured by placing electrodes at various points on the body. They carry the currents…
-
Sources of Biomedical Signals
Biomedical signals/physiological signals are those signals (phenomenon that conveys information) which are used primarily for extracting information on a biological system under investigation. Our body produces various physiological signals. The accessibility to these signals is important because these signals: All physiological signals can grouped as: A transducer converts a physical signal into an electrical output.…