Liquid Crystal Display Monitor Research Articles

A novel MXene coated liquid crystal display anode derived from a futile computer monitor for microbial fuel cell application

A Ti3C2Tx MXene nanosheet-coated liquid crystal display (LCD) anode is meticulously crafted through precision waterjet cutting, salvaging a discarded LCD monitor. This technique, preserving structural integrity and enhanced electrical conductivity, sets it apart from conventional methods. The resulting MXene-coated LCD anode is well-suited for microbial fuel cell (MFC) applications. Comparative assessments against costlier carbonaceous electrodes like graphite felt and carbon cloth, emphasize that the water-jet cut LCD anode with Ti3C2Tx MXene coating is 3.79 and 2.51 times more cost-effective, with an approximate total cost of $38/m2. Substituting Ti3C2Tx MXene-coated LCD for carbon cloth and graphite felt anodes reduces MFC unit fabrication costs by 19 and 10.45 %, respectively. Notably, the Ti3C2Tx MXene LCD anode-based MFC unit boasts a power density per unit cost of 0.008 W/m2/$, underscoring economic viability. This research highlights waterjet cutting's pivotal role in crafting Ti3C2Tx MXene LCD anodes, opening avenues for scalable, cost-effective electrode production in renewable energy applications.

Recaptured attack-resilient watermarking scheme

We propose a recaptured attack-resilient blind watermarking scheme. The work aims to recover the watermark information from the stego (watermarked image) reacquired through a digital liquid-crystal display monitor. In the age of digital globalization, problems like copyright and integrity infringement of digital content are growing exponentially. The content owner can prove their ownership by extracting the embedded watermark from the digitally breached data. The presented framework is robust to several geometrical and signal processing attacks, including lens distortions, intensity distortion, and moiré distortion caused by recapture attack. The singular values of a watermark image and a unique security key are embedded in the host image’s double-density dual-tree discrete wavelet transform (DDD-DWT) coefficients. However, most singular value decomposition (SVD) based watermarking algorithms are prone to false alarm rates and missed alarm rates, causing a security issue. On that account, the proposed watermarking scheme in this paper introduces a unique security key embedding for authentication at the decoder side. The experimental results show that the proposed framework provides high perceptibility with a WPSNR value >59 dB and robustness against various attacks and security.

The effect of prior knowledge of color on reaction time depends on visual modality

Prior knowledge of color, such as traffic rules (blue/green and red mean “go” and “stop” respectively), can influence reaction times (RTs). Specifically, in a Go/No-go task, where signals were presented by a light-emitting diode (LED) lighting device, RT has been reported to be longer when responding to a red signal and withholding the response to a blue signal (Red Go/Blue No-go task) than when responding to a blue signal and withholding the response to a red signal (Blue Go/Red No-go task). In recent years, a driving simulator has been shown to be effective in evaluation and training of driving skills of dementia and stroke patients. However, it is unknown whether the change in RT observed with the LED lighting device can be replicated with a monitor presenting signals that are different from the real traffic lights in terms of depth and texture. The purpose of this study was to elucidate whether a difference in visual modality (LED and monitor) influences the effect of prior knowledge of color on RTs.Fifteen participants performed a simple reaction task (Blue and Red signals), a Blue Go/Red No-go task, and a Red Go/Blue No-go task. Signals were presented from an LED lighting device (Light condition) and a liquid crystal display (LCD) monitor (Monitor condition).The results showed that there was no significant difference in simple RT by signal color in both conditions. In the Go/No-go task, there was a significant interaction between the type of signal presentation device and the color of signal. Although the RT was significantly longer in the Red Go/Blue No-go than Blue Go/Red No-go task in the Light condition, there was no significant difference in RT between the Blue Go/Red No-go and Red Go/Blue No-go tasks in the Monitor condition.It is interpreted that blue and red signals presented from the LCD monitor were insufficient to evoke a perception of traffic lights as compared to the LED. This study suggests that a difference in the presentation modality (LED and monitor) of visual information can influence the level of object perception and consequently the effect of prior knowledge on behavioral responses.

A Multi-Disciplinary Optimization Approach to Eco-Friendly Design Using the Response Surface Method

From a life-cycle perspective, the design stage is the key to controlling the environmental impacts of a product because at this stage, all the different parameters can be optimized to realize the required functions while ensuring that the product is environmentally friendly. Here, it is proposed that the optimization of an eco-design should be completed during the concept design stage to strike a balance between the environmental impacts and mechanical property requirements of the product. In this study, experimental data for these two parameters were first obtained via life-cycle assessments and von Mises stress analyses, respectively. Next, the response surface method was adopted to acquire the approximation functions. Finally, a genetic algorithm was employed for multi-objective optimization to realize the eco-design of the product. The proposed methodology was illustrated and evaluated by taking a liquid crystal display monitor design as an example. The results show that material thickness of the mirror is a key parameter that affects both objectives of the product. Although the mechanical properties of ABS are slightly worse than that of PS, it is the best choice for multi-objective optimization while considering the environmental impact at the same time.

Immersive reading in virtual and augmented reality environment

Purpose This study aims to investigate “immersive reading,” which occurs when individuals read text while in a virtual reality (VR) or augmented reality (AR) environment. Design/methodology/approach In Experiment 1, 64 participants read text passages and answered multiple-choice questions in VR and AR head-mounted displays (HMDs) compared with doing the same task on liquid crystal display (LCD). In Experiment 2, 31 participants performed the same reading tasks but with two VR HMDs of different display quality. Findings Compared with reading on LCD as the baseline, participants reading in VR and AR HMDs got 82% (VR) and 88% (AR) of the information accurately. Participants tended to respond more accurately and faster, though not statistically significant, with the VR HMD of higher pixel density in the speed-reading task. Originality/value The authors observed the speed and accuracy of reading in VR and AR environments, compared with the reading speed and accuracy on an LCD monitor. The authors also compared the reading performance on two VR HMDs that differed in display quality but were otherwise similar in every way.

Effect of biological factors on latency of pattern-reversal visual evoked potentials associated with cathode ray tubes and liquid crystal display monitors in normal young subjects.

Owing to several factors, peak latencies of pattern-reversal visual evoked potentials (p-VEP) are delayed when viewing liquid crystal display (LCD) monitors compared to those evoked when viewing cathode ray tube (CRT) monitors. However, few studies have examined whether biological factors affect latency in LCD. This study aimed to investigate whether biological factors caused latency changes in LCD among young subjects. Twenty-eight subjects (56 eyes) aged 21-29years (mean ± SD, 22.7 ± 1.7) participated in this study. We recorded output from each eye twice for both CRT and LCD monitors under the same conditions for monocular p-VEP. The peak latencies of three components (N75, P100, and N145) were compared between these two monitors. All peak latencies recorded with LCD were delayed compared to those recorded with CRT: N75, 9.7 ± 2.5ms; P100, 10.1 ± 3.0ms; and N145, 8.4 ± 6.2ms (all p < 0.001). The degree of latency delay varied depending on the components. Moreover, all peak latencies of CRT appeared earlier than standard values of N75, P100, and N145. These findings suggest that the following aspects should be considered when assessing biological factors that may affect latency: components might influence latency changes; a young age could be related to an early appearance of peak latencies; inter-individual differences might cause latency change. These biological factors should be considered as possible causes for the varying latencies in an LCD monitor. Further studies should include healthy adults with a wider age range to assess the effects of age on latency.

Detectability of the diagonal direction in the assessment of medical images using a high-brightness liquid crystal display monitor.

Liquid crystal display (LCD) monitors show a homogenous quadratic pattern in the number of pixels, size, and dimensions. However, their modulation transfer function (MTF) has a non-isotropic effect in the vertical, horizontal, and diagonal directions on the screen from the shape and pattern of arrangement of pixels. Moreover, the MTF of the human eye differs in spatial frequency response directivity among individuals. In this study, the high-brightness LCD monitor detectability was physically simulated and visually examined throughout the system, including the imaging system. Furthermore, the influence of anisotropy of the LCD monitor was evaluated.The MTF of the LCD monitor was measured by acquiring a bar pattern using a digital camera with sufficiently small pixels in the vertical, horizontal, and diagonal directions and by performing interpolation processing through waveform reproduction and frequency analysis. The detectability of the LCD monitor was verified throughout the system, including the imaging system. Radiographs of the rectangular wave chart (0.5-10 LP/mm) were obtained in the vertical, horizontal, and diagonal (45°) directions to assess the perceivable limit of the human eye (LP/mm).The spatial resolution of the LCD monitor in the diagonal direction was higher than that in the vertical or horizontal direction, which was in good agreement with the results of the profile analysis and visual evaluation.

Dogs (Canis familiaris) Gaze at Our Hands: A Preliminary Eye-Tracker Experiment on Selective Attention in Dogs.

Simple SummaryDogs seem to communicate with humans successfully by getting social information from body signals such as hand signs. However, less is known regarding how dogs pay attention visually toward human body signals including hand signs. The objective of this pilot study was to reveal dogs’ social visual attention tuned to inter-species communication with humans by comparing gazing patterns to the whole body of human, dogs, and cats. The pictures showing humans with or without hand signs, dogs, and cats were presented on a liquid crystal display monitor, and gazing behaviors of subject dogs to these pictures were recorded by an eye-tracking device. The subjects gazed at human limns more frequently than limbs within conspecifics and cat images, where the dogs attention were focused on the head and body. Furthermore, gaze toward hands was greater in the human hand sign photos relative to photos where human hand signs were not present. These results indicate that dogs have an attentional style specialized for human non-verbal communication, with an emphasis placed on human hand gestures.Dogs have developed a social competence tuned to communicate with human and acquire social information from body signals as well as facial expressions. However, less is known regarding how dogs shift attention toward human body signals, specifically hand signs. Comparison among visual attentional patterns of dogs toward whole body of human being, conspecifics, and other species will reveal dogs’ basic social competences and those specialized to inter-species communication with humans. The present study investigated dogs’ gazing behaviors in three conditions: viewing humans with or without hand signs, viewing conspecifics, and viewing cats. Digital color photographs were presented on a liquid crystal display monitor, and subject dogs viewed the images while their eyes were tracked. Results revealed that subjects gazed at human limbs more than limbs within conspecific and cat images, where attention was predominately focused on the head and body. Furthermore, gaze toward hands was greater in the human hand sign photos relative to photos where human hand signs were not present. These results indicate that dogs have an attentional style specialized for human non-verbal communication, with an emphasis placed on human hand gestures.

Role of ambient light in the detection of contrast elements in digital dental radiography

This study aimed to evaluate the effect of different ambient light levels on observer detection of small contrast differences in a contrast phantom by using a high-end liquid crystal display (LCD) monitor. An aluminum step wedge was converted into a contrast phantom by the addition of bore holes. Radiographic images of the contrast elements were presented to 20 observers. Images were displayed in random order under different ambient light levels (0, 50, 200, and 500 lux) twice, and the observers had to determine if contrast elements were visible. Sensitivity and specificity were determined to calculate areas under receiver operating characteristic curves and Friedmann's test was applied to evaluate the influence of the ambient light level on observer performance. Mean AZ values were moderate for each ambient light level at 0.715, 0.793, 0.764, and 0.722 for 0, 50, 200, and 500 lux, respectively. The influence of the ambient light level on observer performance was not statistically significant (P > .05). There was no significant influence of ambient light between 0 and 500lux on observer ability to detect small contrast details displayed on a high-end LCD monitor.

Enhancement of measurement accuracy of optical stereo deflectometry based on imaging model analysis

This paper represents a novel analysis method to improve the measurement accuracy of an optical stereo deflectometry system. A novel imaging model is proposed to research the relation between the phase uncertainty and the normal uncertainty of a stereo deflectometry system. By comprehensively considering the influence on the sampling phase error and the normal error, the system's screen pixel size and the period of fringe displayed on the screen are analyzed to enhance the measurement accuracy. To verify the proposed method, experiments using a common LCD (liquid crystal display) monitor and a screen with Retina Display have been investigated respectively. Experimental results demonstrate using the screen with Retina Display can significantly improve the measurement accuracy of a stereo deflectometry 2.38 times in accuracy due to the ultra-fine pixel size. A stereo deflectometry system based on the proposed method has been built to measure a standard flat mirror and a standard concave mirror. The global measurement accuracy of the flat mirror and the concave mirror can reach 69.7 nm and 96.8 nm respectively.

S109. Difference of visual evoked potential study with different types of monitors

Introduction Pattern reversal visual evoked potentials (VEPs) study was traditionally done with cathode ray tube (CRT) monitor, however CRT monitors has been rapidly replaced with liquid crystal display (LCD) monitor. So, we wanted to test that LCD monitor can be used for pattern reversal VEPs with short response time instead of CRT monitor. Methods In 8 normal subjects with 16 eyes, VEPs were done with CRT and response time 1 ms LCD, 5 ms LCD monitors. Latencies of P100 waves and amplitudes of N75-P100 were compared for 3 different monitor groups. Results Mean latencies of P100 waves were 111.8 ± 6.0 ms for CRT group, 115.8 ± 5.9 ms for 1 ms LCD group and 118.5 ± 6.2 ms for 5 ms LCD group and there was significant difference between latencies of CRT and 5 ms groups (p Conclusion Latency of P100 wave with LCD monitor with 5 ms response time which is popular in use is longer than that with CRT monitor and LCD monitor with 1 ms response time also showed tendency of delay. These results suggest that the ready-made reference latency value with CRT monitor should not be applied to the reference range with LCD monitor even though short response time.

Evaluation of a new test pattern for daily quality assurance of medical display monitors

Introduction In the visual evaluation of daily quality assurance (QA) of medical display monitors, some well-established test patterns are available; however, the same pattern is always used. Therefore, it is difficult to detect luminance deterioration. Purpose We developed the new software for the daily QA of monitors (mdQA), in which randomized object (RO) patterns were generated. The RO patterns had a low-contrast object consisting of a randomly located sphere. In the present study, we evaluated whether these RO patterns can detect luminance deterioration. Materials and methods The mdQA was developed using Microsoft Visual Basic 2010 Express. The digital driving level (DDL) and the standard deviation (SD) of the RO pattern background, as well as the size and contrast of the object, were adjustable. In this study, the DDL and SD were set at 130 and 20, respectively. The object diameter was determined at 30 pixels. Contrast values varied from 4 to 8 pixels. We produced 40 patterns with and without the object using the mdQA. A receiver operating characteristic analysis was performed for the two different display luminance (400 and 320 cd/m 2 ) using a 2-megapixel color liquid crystal display (LCD) monitor. Ten radiation therapists observed the patterns and scored the confidence rate using a continuous scale. Results There was a statistically significant difference between the two LCD monitor conditions ( p Conclusion The developed mdQA enables the creation of RO patterns for the daily QA of medical display monitors; these RO patterns are useful in detecting luminance deterioration. Disclosure None.

Method for out-of-focus camera calibration.

State-of-the-art camera calibration methods assume that the camera is at least nearly in focus and thus fail if the camera is substantially defocused. This paper presents a method which enables the accurate calibration of an out-of-focus camera. Specifically, the proposed method uses a digital display (e.g.,liquid crystal display monitor) to generate fringe patterns that encode feature points into the carrier phase; these feature points can be accurately recovered, even if the fringe patterns are substantially blurred (i.e., the camera is substantially defocused). Experiments demonstrated that the proposed method can accurately calibrate a camera regardless of the amount of defocusing: the focal length difference is approximately 0.2% when the camera is focused compared to when the camera is substantially defocused.

A Feasibility Study of Smartphone-Based Telesonography for Evaluating Cardiac Dynamic Function and Diagnosing Acute Appendicitis with Control of the Image Quality of the Transmitted Videos

Our aim was to prove the feasibility of the remote interpretation of real-time transmitted ultrasound videos of dynamic and static organs using a smartphone with control of the image quality given a limited internet connection speed. For this study, 100 cases of echocardiography videos (dynamic organ)-50 with an ejection fraction (EF) of ≥50s and 50 with EF <50%-and 100 cases of suspected pediatric appendicitis (static organ)-50 with signs of acute appendicitis and 50 with no findings of appendicitis-were consecutively selected. Twelve reviewers reviewed the original videos using the liquid crystal display (LCD) monitor of an ultrasound machine and using a smartphone, to which the images were transmitted from the ultrasound machine. The resolution of the transmitted echocardiography videos was reduced by approximately 20% to increase the frame rate of transmission given the limited internet speed. The differences in diagnostic performance between the two devices when evaluating left ventricular (LV) systolic function by measuring the EF and when evaluating the presence of acute appendicitis were investigated using a five-point Likert scale. The average areas under the receiver operating characteristic curves for each reviewer's interpretations using the LCD monitor and smartphone were respectively 0.968 (0.949-0.986) and 0.963 (0.945-0.982) (P = 0.548) for echocardiography and 0.972 (0.954-0.989) and 0.966 (0.947-0.984) (P = 0.175) for abdominal ultrasonography. We confirmed the feasibility of remotely interpreting ultrasound images using smartphones, specifically for evaluating LV function and diagnosing pediatric acute appendicitis; the images were transferred from the ultrasound machine using image quality-controlled telesonography.

Usability Evaluation of VR Interface for Mobile Robot Teleoperation

This article presents the results from research in which 3 different remote control interfaces were compared to assess the impact of interface structure on the performance of the operator for remotely controlled mobile inspection robots. The primary control interface of a mobile robot consists of a head-mounted display, data gloves for gripper control, joystick for movement control of the robot platform, and a motion tracking system for measuring head orientation and hand position. In order to compare different control interfaces, an additional system, based on a Liquid Crystal Display monitor and joystick, was prepared. Results of this study show that the use of virtual reality techniques in the interfaces of mobile inspection robots increases operator productivity, the level of spatial presence, and distance evaluation while facilitating the execution of tasks, as well as improving and speeding up their execution and reducing the operator’s time needed to adapt to the control interface. The latter is achieved with the increased level of intuitive control while ensuring comfort.

Efficacy of a pressure-sensing mattress cover system for reducing interface pressure: study protocol for a randomized controlled trial.

BackgroundInterface pressure is a key risk factor in the development of pressure ulcers. Visual feedback of continuous interface pressure between the body and support surface could inform clinicians on repositioning strategies and play a key role in an overall strategy for the prevention and management of pressure ulcers.Methods/DesignA parallel two-group randomized controlled clinical trial will be conducted to study the effect of continuous pressure imaging on reducing interface pressure and on the incidence of pressure ulcers in vulnerable hospital patients. A total of 678 eligible consenting inpatients at risk of pressure ulcer development in a tertiary acute care institution will be randomly allocated to either having the ForeSite PT™ system with the liquid-crystal display monitor turned on to provide visual feedback to the clinicians while also collecting continuous interface pressure data (intervention group) or to having the ForeSite PT™ system with monitor turned off (that is, not providing visual feedback) but still collecting continuous interface pressure data (control group), in a ratio of 1:1. Continuous interface pressure data will be collected in both groups for 3 days (72 h). Data collection will continue until discharge for a subset of approximately 60 patients. The primary outcome will be the differences in the two groups’ interface pressure analysis. Interface pressure readings will be collected through hourly samplings of continuous interface pressure recordings. Secondary outcomes will be the differences between the two groups in pressure-related skin and soft tissue changes in areas at risk of pressure ulcer (obtained at baseline within 24 h of admission) and on the third day of the trial or at discharge and perceptions of the intervention by patients and clinicians (obtained on the third day or at discharge).DiscussionThis will be the first randomized controlled trial to investigate the effect of visual feedback with continuous interface pressure of vulnerable hospital patients across different care settings, and the association between interface pressure and development of pressure-related skin and soft tissue changes. The results could provide important information to guide clinical practice in the prevention and management of pressure ulcers.Trials registrationClinicalTrials.gov NCT02325388 (date of registration: 24 December 2014).

An LCD-VCOM-Noise Resilient Mutual-Capacitive Touch-Sensor IC Chip With a Low-Voltage Driving Signal

A mutual-capacitive touch-sensor read-out integrated circuit (ROIC) with a differential sensing scheme is proposed to reduce the driving pulse amplitude of touch sensor panel (TSP) down to 0.4 V. This reduction is achieved by mitigating the effect of the liquid crystal display (LCD) common-voltage (VCOM) noise, which is time periodic. To accomplish this mitigation, the TSP driving pulse (VSTM) is synchronized to the gate-driver-pulse generating signal (GCLK) of LCD, and its frequency is set to (2n + 1) times the frequency of GCLK, where n is a non-negative integer. The repetition period TN of the VCOM noise is one half of the GCLK period. A receiver channel consists of a charge amplifier, a chopper, and an integrator; all are in differential circuits. The chopper is driven by the VSTM. The integration period of the integrator is set to 2T N to suppress the periodic LCD noise. A referenceless clock and data recovery circuit are used to generate VSTM from GCLK continuously with time in spite of the discontinuity of GCLK during the vertical blanking period. The proposed ROIC fabricated in a 0.35-μm CMOS was applied to a 6.9 in 12 × 16 TSP located on a rather noisy 23 in in-plane switching LCD monitor. The measured signal-to-noise ratio changes from 27 to 9 dB as the VSTM amplitude changes from 3.3 to 0.4 V, where the GCLK frequency is 16.8 kHz and the VSTM frequency is 352.8 kHz. The reporting rate of the ROIC is 175 Hz.

WE-D-204-03: A Six-Year Longitudinal Evaluation of the DICOM GSDF Conformance Stability of LCD Monitors

Purpose: The calibration of monitors in radiology is critical to ensure a standardized reading environment. If left unchecked, monitors initially calibrated to follow the DICOM Grayscale Standard Display Function (GSDF) can fall out of calibration. This work presents a quantitative evaluation of the stability of a cohort of monitors with similar deployment times and clinical utilization. Methods: Fifty-four liquid crystal display (LCD) monitors (NEC L200ME) were deployed for clinical use in 2009. At that time, a subset of eight of these monitors were used to generate a look-up table (LUT) using the open-source software pacsDisplay. The software was used to load the LUT to the graphics card of the computer in order to make the monitors compliant with the GSDF. The luminance response of the monitors was evaluated twice over six years, once in 2011 and again in 2015. Results: As expected, the maximum luminance of the monitors decreased over time, with an average reduction from 2009 of 35% in 2011, and 53% in 2015. The luminance ratio (maximum luminance divided by the minimum) also decreased, with the all of the decrease occurring in the first two years (average 20%). There was an overall increase in relative error compared with the DICOM GSDF from measurement to measurement, indicating that deviation from the GSDF increases with monitor luminance reduction. Along with changes in luminance, several other issues were identified during the testing, including non-uniformities, bad pixels, and missing calibration software. Conclusion: From the initial installation of these monitors, most of the degradation occurred during the first two years, highlighting the importance of routine clinical testing of displays. Following such quality assurance, displays could be either re-calibrated or replaced depending on different thresholds. In addition, other issues not related to luminance could be identified and corrected.

A Feasibility Study of Real-Time Remote CT Reading for Suspected Acute Appendicitis Using an iPhone

We aimed to evaluate the feasibility of an iPhone-based remote control system as a real-time remote computed tomography (CT) reading tool for suspected appendicitis using a third-generation (3G) network under suboptimal illumination. One hundred twenty abdominal CT scans were selected; 60 had no signs of appendicitis, whereas the remaining 60 had signs of appendicitis. The 16 raters reviewed the images using the liquid crystal display (LCD) monitor of a picture archiving and communication system (PACS) workstation, as well as using an iPhone connected to the PACS workstation via a remote control system. We graded the probability of the presence of acute appendicitis for each examination using a five-point Likert scale. The overall sensitivity and specificity for the diagnosis of suspected appendicitis using the iPhone and the LCD monitor were high, and they were not significantly different (sensitivity P = 1.00, specificity P = 0.14). The average areas under the receiver operating characteristic curves for all CT readings with the iPhone and LCD monitor were 0.978 (confidence interval 0.965-0.991) and 0.974 (0.960-0.988), respectively, and the two devices did not have significantly different diagnostic performances (P = 0.55). The inter-rater agreement for both devices was very good; the kappa value for the iPhone was 0.809 (0.793-0.826), and that for the LCD monitor was 0.817 (0.801-0.834). Each rater had moderate-to-very good intra-observer agreement between the two devices. We verified the feasibility of an iPhone-based remote control system as a real-time remote CT reading tool for identifying suspected appendicitis using a 3G network and suboptimal illumination.

医用液晶ディスプレイと汎用液晶ディスプレイにおける視覚的評価─胸部CT 画像とモノクロ，カラー表示における核医学画像の模擬信号の検出能─

The purpose of this study was to evaluate the detection performance of simulated nodules in chest computed tomography (CT) images and nuclear medicine images with an ordinary liquid crystal display (LCD) and a medical LCD (grayscale standard display function: GSDF) and gamma 2.2. We collected 72 chest CT image slices obtained from an LSCT phantom with simulated signals composed of various sizes and CT values and 78 slices of monochrome and color nuclear medicine images obtained from a digital phantom with a simulated signal composed of various sizes and radiation levels. Six observers performed receiver operating characteristic (ROC) analysis using a continuous scale. The area under the ROC curve (AUC) was calculated for each monitor. The average AUC values for detection of chest CT images on a medical LCD (GSDF), medical LCD (gamma 2.2), and ordinary LCD were 0.71, 0.67, and 0.73, respectively. The average AUC values for detection of monochrome nuclear medicine images using a medical LCD (GSDF), medical LCD (gamma 2.2), and ordinary LCD were 0.81, 0.75, and 0.72, respectively. The average AUC values for detection of color nuclear medicine images on a medical LCD (GSDF), medical LCD (gamma 2.2), and ordinary LCD were 0.88, 0.86, and 0.90, respectively. Observer performance for detection of simulated nodules in chest CT images and nuclear medicine images was not significantly different between the three LCD monitors. We therefore conclude that an ordinary LCD monitor can be used to detect simulated nodules in chest CT images and nuclear medicine images.