Technical description of ENTviewer
ENTviewer is an electronic and optical device. It comprises a spatula with a video camera as well as a base used for signal reception. A compact camera (1/8″ matrix) is placed at the end of the spatula and registers the image with the resolution of 800×600 pixels. The camera lens is covered with a sapphire glass and a steel spatula frame. The video image from the spatula is transmitted to the base wirelessly via radio. The spatula contains a broadband analogue transmitter using the FM modulation and frequency range of 2.4 GHz. The examined object is lit by two white LED diodes with the optimally matched colour temperature and light intensity. Additionally, the light may be modulated with the examined patient’s voice frequency, which results in a strobing effect allowing for a laryngostroboscopic examination. The patient’s voice is intercepted by a highly sensitive condenser microphone placed in the upper part of the spatula, just below the camera. Voice frequency measurement algorithm uses a method for detecting the sound waveform and allows for measuring the period with the accuracy of one microsecond, which makes it possible to obtain a smooth vocal cord motion picture in a very slow motion. The speed of vocal cord motion during the examination may be additionally adjusted with the use of a touch panel placed at the back of the spatula or still later with the use of a software. A touch panel uses a capacitive touch detection method as well as an advanced algorithm for detecting various gestures, i.e. a slider or a double click. The entire work of the spatula is governed by a 32-bit microprocessor from the ARM family, equipped in the Cortex M3 core, which allows for performing all the necessary operations while the spatula is on. Moreover, the processor guarantees high energy-efficiency. The spatula is powered by a li-ion battery with the capacity of 330 mAh, which allows for approximately one hour of continuous operation. The battery is charged wirelessly with the use of inductive charger – in the central part of the spatula a telecoil was placed, made of six layers of paths marked on the printed circuit board (PCB). The charging process is governed by one of the latest systems by Linear Technology, a leader in manufacturing advanced power systems. A transmitting element of the inductive charger was made with the use of a high-power parallel resonant circuit. It allows for a wireless transmission of charging energy even at a distance of several centimetres.
The spatula casing was made with the use of nontoxic certified high quality PC medical material. Moreover, the casing is reinforced with a frame made of surgical stainless steel.
The base of ENTviewer serves as an image receptor, charger and spatula heater (to avoid fogging of optical elements). A video signal receiver is compatible with the transmitter placed in the spatula and ensures reception of video signal which is then digitalised and transmitted to the computer via the USB interface. The spatula heater maintains a constant temperature of about 38ºC. It is made of heating elements and a precise temperature sensor. Additionally, a thermal fuse is included to protect the system against a potential overheating. Inside the base, a highly efficient switch mode power supply meeting the requirements for use in medical devices was placed.
Recently, our offer has been extended by model M and MS, i.e. a portable version which is equally functional as the desktop model (model L and LS), only it was placed in a small, handy suitcase that allows for easy and fast transfer.
Soon we are going to present also the top-of-the-range model of ENTviewer MCS, with embedded computer to eliminate the need for having a separate PC.
Also in preparation are otoscope and rhynoscope tips for ear and nose examination.