Claim Missing Document
Check
Articles

Found 5 Documents
Search
Journal : TELKOMNIKA (Telecommunication Computing Electronics and Control)

Graphene Nanoplatelets (GnP)-PVA Based Passive Saturable Absorber Nabihah Hussin; Mohd Haniff Ibrahim; Fauzan Ahmad; Hafizal Yahaya; Sulaiman Wadi Harun
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 15, No 2: June 2017
Publisher : Universitas Ahmad Dahlan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12928/telkomnika.v15i2.6126

Abstract

A passive Q-switched pulsed laser at 1.5 m region incorporating graphene nanoplatelets (GnPs) embedded in Polyvinyl Alcohol (PVA) is demonstrated. A surfactant is used to aid the dispersion of the GnPs before it is mixed with PVA to develop a GnPs-PVA film based SA. The SA is integrated into the laser cavity by attaching a cut of the GnPs-PVA film in between two fiber ferrule of the laser ring cavity.The proposed GnPs-PVA film based passive Q–switched laser was able to operate as the input pump power was increased from 39 mW up to a maximum of 148 mW before diminishing. The laser obtained operated with a central wavelength of 1530.76 nm. Repetition rates were obtained at 33 kHz to 91.5 kHz, throughout the tunable input pump power with the shortest pulse width of 2.42 s. Maximum attainable peak power and pulse energy of 1.2 mW and 5.9 nJ, respectively, was recorded, accompanied by a signal to noise ratio (SNR) of 28 dB.
Discrete liquid level fiber sensor Muhammad Yusof Mohd Noor; Ahmad Sharmi Abdullah; Asrul Izam Azmi; Mohd Haniff Ibrahim; Mohd Rashidi Salim; Norazan Kassim
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 17, No 4: August 2019
Publisher : Universitas Ahmad Dahlan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12928/telkomnika.v17i4.12769

Abstract

A novel simple fiber sensor to sense liquid level is presented. The operation principle is based on the relative Fresnel reflective intensity. The sensor consists of a fiber splitter with the configuration of one input to multiple fiber outputs, i.e. 1×4, 1×8 and 1×12 arrangements that act as a discrete liquid level. A broadband source (BBS) is used as the light source supply. The total reflected power intensity is measured using a power meter. Experimental results show that the power intensity decreases as the level of liquid is increased. The sensor has a simple configuration, low cost, and it can be customized for a wide height measurement range spanning from a few centimeters up to a hundred meters.
Varying Effects of Temperature and Path-length on Ozone Absorption Cross-Section Enenche Patrick; Michael David; A.O. Caroline; Mohd Haniff Ibrahim; Sevia Mahdaliza Idrus; Tay Ching En Marcus
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 16, No 2: April 2018
Publisher : Universitas Ahmad Dahlan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12928/telkomnika.v16i2.8577

Abstract

Inconsistencies in the absorption cross section of ozone have been observed. Hence, for accurate measurement, we have reported the combined effects of varying optical path-length and temperature on the ozone gas absorption cross section (OACS) at 334.15nm. Adopting optical absorption spectroscopy, results of the (OACS) have been simulated using spectralcalc simulator with HITRAN 12 has the latest line list. OACS increased by 52.27% as the temperature increased from 100K to 350K while it was slightly affected by a 0.007% decrease varying the path-length from 0.75cm-130cm.
Fundamental Review to Ozone Gas Sensing Using Optical Fibre Sensors Michael David; Mohd Haniff Ibrahim; Sevia Mahdaliza Idrus; Tay Ching En Marcus
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 13, No 4: December 2015
Publisher : Universitas Ahmad Dahlan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12928/telkomnika.v13i4.2047

Abstract

The manuscript is a review of basic essentials to ozone gas sensing with optical methods. Optical methods are employed to monitor optical absorption, emission, reflectance and scattering of gas samples at specific wavelengths of light spectrum. In the light of their importance in numerous disciplines in analytical sciences, necessary integral information that serves both as a basis and reference material for intending researchers and others in the field is inevitable. This review provides insight into necessary essentials to gas sensing with optical fibre sensors. Ozone gas is chosen as a reference gas. Simulation results for ozone gas absorption cross section in the ultraviolet (UV) region of the spectrum using spectralcalc.com simulation have also been included.
A low-cost fiber based displacement sensor for industrial applications Siti Mahfuza Saimon; Nor Hafizah Ngajikin; Muhammad Shafiq Omar; Mohd Haniff Ibrahim; Muhammad Yusof Mohd Noor; Ahmad Sharmi Abdullah; Mohd Rashidi Salim
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 17, No 2: April 2019
Publisher : Universitas Ahmad Dahlan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12928/telkomnika.v17i2.9754

Abstract

In this paper, a low-cost fiber optic displacement sensor (FODS) using a bundle of plastic optical fiber (POF) as a probe is developed and presented. The sensor consists of a high power light emitting diode (LED) as light source, a probe with multiple receiving plastic optical fiber and a photodiode detector. The sensor is characterized at millimeter distance and the sensor output is analyzed from 0 mm to 13 mm displacement. The sensitivity of the sensor is found to be 5.38 mV/mm over 2.6 mm sensing range. The sensor is very useful for close distance target since it is highly sensitive at the front slope. The low development cost, high degree of sensitivity and simplicity of the design make it suitable for wide range of industrial applications.