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In this paper, an analysis of the complementary CMOS active pixel and readout circuit is carried out. Complementary pixel structure which is different from conventional 3TR APS structure consists of photo diode, reset PMOS, several NMOSs and PMOSs sets for complementary signals. Proposed CMOS image sensors pixel has been fabricated using 0.5 standard CMOS process. Measured results show that the output signal range is from 0.8 V to 3.8 V. This output signal range increased 125 % compared to conventional 3TR pixel in the condition of 5 V power supply.

Integrated circuit of a new neuron chain with a synapse function for Hodgkin-Huxley model which is a good electrical model about a real biological neuron is implemented in a 1 poly 2 metal CMOS technology. Pulse type neuron chain consist of series connected current controlled single neurons through synapses. For the realization of the single neuron, a pair of voltage mode oscillators using operational transconductance amplifiers and capacitors is used. The synapse block which is a connection element between neurons consist of a voltage-current conversion circuit using current mirror. SPICE simulation results of the proposed circuit show 160 mV amplitude pulse output and propagation of the signal through synapses. Measurements of the fabricated pulse type neuron chip in condition of power supply are shown and compared with the simulated results.

We propose a new image pixel architecture which has OFD(Over Flow Device) node by improving conventional 3TR pixel structure. Newly designed pixel consists of photo diode which is verified with HSPICE simulation, PMOS reset transistor, several NMOS and several PMOS transistors. Photodiode signals from each PMOS and NMOS are detected by Reset PMOS. These output signals give enough chances to detect wide operation coverage because OFD node has overflow photocurrent. According to various light intensity, we analyzed characteristic of the output voltage with a SPICE tool. Proposed pixel output has specific value which can detect possible from to light intensity. It has wide-dynamic range of 160 dB.

In this paper, we propose a new complementary image sensor pixel structure by improving the conventional 3TR pixel structure. Proposed complementary pixel structure for wide dynamic range CIS consists of photo diode, PMOS reset transistor, several PMOS and NMOS transistors for complementary signals. We show SPICE simulation results of the complementary image pixel structure for optimization. Proposed complementary pixel was fabricated with 0.5 µm 1-poly 2-metal standard CMOS process. From the measured results, output voltage of the proposed pixel is 0.8 V to 3.8 V in condition of the 5 V power supply. These output signals give enough chances to detect wide operation coverage.

Purpose: To compare the accuracy of refractive outcome measured by Ultrascan (Alcon, Fort Worth, TX, USA) and partial coherence interferometers after phacovitrectomy. Methods: We performed a retrospective study in 74 eyes of 74 patients who underwent phacovitrectomy. SRK-T formula was used to predict intraocular lens (IOL) power. The difference between the predicted and postoperative refractive outcomes for the 2 methodologies (Ultrascan and IOL Master [Zeiss, Carl Zeiss, Jena, Germany]) were compared. The predicted refractive outcome was defined as the estimated refractive error when the selected IOL was inserted. Results: The axial length measured using IOL Master was statistically longer than when measured using Ultrascan (23.85 ± 0.15 mm, 23.56 ± 0.15 mm, p < 0.001). Based on keratometry, statistically significant difference between the 2 groups was not observed. The postoperative refractive error was more accurate when using the IOL Master than Ultrascan (0.08 ± 0.74, 0.47 ± 0.69, p < 0.001). However, in cases of vitreous hemorrhage, the postoperative refractive error was 0.42 ± 0.49 with the IOL Master and 0.07 ± 0.54 with the Ultrascan. Conclusions: Generally, IOL Master is a more accurate method for calculating the IOL power prior to phacovitrectomy. However, in cases of vitreous hemorrhage, Ultrascan appears superior to IOL Master when calculating the IOL power. J Korean Ophthalmol Soc 2015;56(7):1059-1064