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1.
J Transl Med ; 17(1): 46, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30767763

RESUMO

BACKGROUND: Although previous prevalence studies of DED were reported from some countries worldwide, national data are unavailable in China. We aimed to conduct an up-to-date national survey on the prevalence of DED in China and find out the potential risk factors including air pollutant. METHODS: 23,922 eligible outpatients were recruited from ophthalmic clinics of 32 cities in China in 2013 by registration orders. The patients' demographic characteristics, history of keratorefractive surgery, diseases and medication history were collected and the daily air pollutant data in 2013. Multivariate logistic analysis was performed to identify the potential risk factors associated with DED. The association between related factors and dry eye diseases subtypes evaluated as p value and odds ratios (OR) with 95% confidence intervals (CI). RESULTS: Among 23,922 outpatients, the prevalence of DED was 61.57%, and that of the male patients was 57.64% and of the female was 65.32% (P < 0.0001). Multivariate logistic regression suggested that the possible risk factors for DED included: female, older age, history of keratorefractive surgery, presence of arthritis, thyroid diseases, and antihistamine, diuretic, duodenal ulcer drugs, diazepam. Air pollutants including O3, PM2.5, and SO2 were also identified as the risk factors. CONCLUSION: The prevalence of DED among ophthalmic outpatients in China was considerably high. Age, gender, history of keratorefractive surgery, diseases, medication history, and air pollutants were associated with DED prevalence.


Assuntos
Poluentes Atmosféricos/toxicidade , Síndromes do Olho Seco/epidemiologia , Oftalmologia , Pacientes Ambulatoriais , População Urbana , Adulto , China/epidemiologia , Cidades , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prevalência , Fatores de Risco
2.
BMJ Open ; 9(12): e028458, 2019 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-31892642

RESUMO

OBJECTIVE: To evaluate the association between health literacy (HL) and quality of life (QOL) among cancer survivors in China. DESIGN: Cross-sectional study in China. SETTING AND PARTICIPANTS: This is a cross-sectional observational study of 4589 cancer survivors aged 18 years and older from the Shanghai Cancer Rehabilitation Club. Participants were enrolled and completed the questionnaires between May and July 2017. MEASUREMENT: HL was assessed by three established screening questions and QOL was evaluated using the simplified Chinese version of the European Organisation for Research and Treatment of Cancer Quality-of-Life Questionnaire-Core 30 items. Answers to all questionnaires were collected through face-to-face interviews or through self-administered questionnaires for literate participants. Participants were excluded if they did not answer any one of the HL questions. Baseline characteristics were compared by levels of HL using χ2 test for categorical variables and Wilcoxon rank-sum test for non-normal continuous variables. The item response theory (IRT) was used to evaluate the existing measure of HL. Linear regression and logistic regression models were used to investigate the association between HL and QOL. SAS V.9.4 and MULTILOG V.7.03 were used in the analysis. RESULTS: There were 4589 participants included in the study. The calculated results of IRT scale parameters of HL entries indicate that the entries have better discrimination and difficulty. Of the 4589 respondents, 159 (3.5%) had low HL. After adjusting for sociodemographic characteristics, treatment regimen and years with cancers, for each one-point decrement in HL score the QOL score increased by 2.07 (p<0.001). Cancer survivors with low HL were less likely than those with adequate HL to achieve better QOL. In logistic regression, low HL was independently associated with poor QOL (adjusted OR, 2.81; 95% CI 1.94 to 4.06; p<0.001). CONCLUSIONS: Low HL was independently associated with poor QOL among cancer survivors of the Shanghai Cancer Rehabilitation Club.


Assuntos
Sobreviventes de Câncer/psicologia , Letramento em Saúde , Qualidade de Vida/psicologia , Idoso , China , Estudos Transversais , Feminino , Humanos , Modelos Lineares , Modelos Logísticos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
3.
BMC Oral Health ; 18(1): 111, 2018 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-29921269

RESUMO

BACKGROUND: This study aims to understand the deciduous dental caries status of preschool children in Xuhui District of Shanghai, China and to analyze the associated risk factors. METHODS: In January of 2016, a cross-sectional investigation was conducted to examine the oral health of all the kindergarten children in Xuihui District of Shanghai, China. Meanwhile, a field questionnaire survey was conducted with the children's guardians to ascertain the potential risk factors associated with deciduous dental caries. RESULTS: Among 11,153 children, the prevalence of deciduous dental caries was 47.02%, and the mean dmft score was 2.21. The first three predilection sites were maxillary central primary incisors, mandible second primary molars, and mandible first primary molars. There were statistically significant differences in caries prevalence and dmft among different age groups and different household registration (Hukou) types (P < 0.001). Multivariate Logistic regression suggested that the possible risk factors for deciduous caries included: older age, drinking sweetened beverages frequently, often or usually eating sweets before sleep compared to rarely/never eat them at this time, exclusive or predominant breastfeeding compared to exclusive or predominant artificial feeding and latter introduction of toothbrushing. On the other hand, Shanghai Hukou families, high educational level of guardians (high school or college education), regular parental support for children's toothbrushing, guardians' oral health knowledge, and a good perception about children's oral health conditions were shown as potential protective factors for deciduous dental caries. CONCLUSIONS: The deciduous dental caries status of preschool children in Xuhui District of Shanghai was still serious. The caries prevalence in Xuhui, China, is associated with children's age, household registration type, oral health habits, feeding habits, guardians' education level, parental perception about children's oral health and knowledge about oral health.


Assuntos
Cárie Dentária/epidemiologia , Dente Decíduo , Fatores Etários , Bebidas Gaseificadas/efeitos adversos , Criança , Pré-Escolar , China/epidemiologia , Estudos Transversais , Índice CPO , Cárie Dentária/etiologia , Dieta Cariogênica/efeitos adversos , Feminino , Humanos , Modelos Logísticos , Masculino , Prevalência , Fatores de Risco , Inquéritos e Questionários
4.
Discov Med ; 25(137): 91-98, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29641971

RESUMO

OBJECTIVE: We conducted a multicenter cohort study to investigate the prognostic value of some commonly-used laboratory indices in advanced pancreatic ductal adenocarcinoma (PDAC). METHODS: A multicenter cohort study was conducted from 2004 to 2013. The associations between laboratory indices and prognosis of advanced PDAC were examined. RESULTS: This cohort consisted of 553 females (36.2%) and 973 males (63.8%). Patients at cancer stage III and IV were 595 (39.0%) and 931 (61.0%), respectively. The median survival of stage III patients was 9.0 months, with 3-, 6-, and 12-month survival rates of 94.5%, 73.4%, and 28.5%, respectively. The median survival of stage IV patients was 5.4 months, with 3-, 6-, and 12-month survival rates of 79.3%, 42.9%, and 15.0%, respectively. In multivariate analyses, primary tumor diameter, low albumin, and elevated CA19-9 were associated with decreased survival for stage III patients. Age, smoking, primary tumor diameter, elevated ALT or AST, low albumin, and elevated CA19-9 were associated with decreased survival for stage IV patients. CONCLUSION: Elevated CA19-9 level, decreased albumin level, and tumor size were associated with worse survival in stage III patients. Meanwhile, advanced age, smoking, and ALT or AST level were negatively correlated to prognosis in stage IV patients.


Assuntos
Carcinoma Ductal Pancreático/mortalidade , Neoplasias Pancreáticas/mortalidade , Fatores Etários , Idoso , Antígeno CA-19-9/sangue , Carcinoma Ductal Pancreático/sangue , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Pancreáticas/sangue , Fumar/efeitos adversos , Taxa de Sobrevida
5.
Health Qual Life Outcomes ; 16(1): 62, 2018 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-29650050

RESUMO

BACKGROUND: Stomach cancer survivors (SCS) often carry the dual burden of the cancer itself and other comorbidities; meanwhile, they are highly motivated to seek health advice about lifestyles to improve their health and quality of life (QOL). The associations of the comorbidity and the consumption of vegetable and fruit with QOL remain even less clear among the SCS. This study aimed to investigate the associations of comorbidities and consumption of fruit and vegetable with QOL among SCS. METHODS: A cross-sectional study was conducted among 969 SCS between April and July 2015 in Shanghai, People's Republic of China. Data were collected using a self-reported questionnaire, which included questions on sociodemographic characteristics, comorbidities and fruit and vegetable consumption, and a simplified Chinese version of the European Organization for Research and Treatment quality of life version 3 (EORTC QLQ-C30) questionnaire. In order to mitigate the bias caused by confounding factors, multiple linear regression models were employed to calculate the adjusted means of QOL scores. RESULTS: The proportion of participants without any comorbidity was only 23.3%, and the most common comorbidity among SCS was digestive diseases (49.8%). Participants with comorbidity generally reported lower scores for global health and functioning subscales and higher scores for symptom in EORTC QLQ-C30 compared to participants without comorbidity, indicating poorer QOL. Higher scores in most functioning subscales and lower scores in some symptoms subscales were found in participants (38.7%) who ate more than 250 g vegetables every day, compared to participants with less vegetable consumption, and in participants (58.1%) who ate fruit every day, compared to participants who didn't eat fruit every day indicating better QOL. CONCLUSIONS: The comorbidities are common health problems among SCS and have significantly negative influence on QOL, and participants with comorbidities generally reported lower QOL scores. The enough vegetables and fruit consumption are positively associated with QOL of SCS. These findings suggested that a multidisciplinary team approach and a variety of delivery systems are needed to address the medical, psychosocial, and lifestyle components for enriching patient-centered care among SCS.


Assuntos
Sobreviventes de Câncer/psicologia , Frutas , Qualidade de Vida/psicologia , Neoplasias Gástricas/epidemiologia , Verduras , Adulto , Idoso , Sobreviventes de Câncer/estatística & dados numéricos , China , Comorbidade , Estudos Transversais , Feminino , Preferências Alimentares/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Gástricas/psicologia , Inquéritos e Questionários
6.
Sci Rep ; 8(1): 3022, 2018 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-29445094

RESUMO

To examine the association between BMI and QOL in breast cancer survivors in China, we conducted a cross-sectional survey and recruited 10708 breast cancer survivors. Survivors self-reported QOL was measured using the EORTC QLQ-C30 and the QLQ-BR23. The impact of BMI on QOL was examined through standard least squares regression. Normal weight and overweight survivors were more likely to have a better QOL than underweight and obese survivors and the results were similar to survivors diagnosed as having chronic diseases. After adjustment for clinical and sociodemographic factors, the QOL increased with increasing BMI in breast cancer survivors ranged from underweight to overweight with no chronic diseases, especially in the scales of emotional function and fatigue. Obese breast cancer survivors reported a significantly worse QOL compared to normal weight and overweight breast cancer survivors. Within breast cancer survivors with one or more chronic diseases, it was more obvious that overweight ones had a significantly better QOL with clear evidence of a dose relationship across underweight to overweight in almost all scales. Unlike obese breast cancer survivors without chronic diseases, the ones with chronic disease(s) had a similar QOL compared to normal weight breast cancer survivors in all scales except in the domain of fatigue.


Assuntos
Sobreviventes de Câncer/psicologia , Sobrepeso/psicologia , Qualidade de Vida/psicologia , Índice de Massa Corporal , Peso Corporal , Mama/patologia , Neoplasias da Mama/psicologia , China , Doença Crônica , Comorbidade , Estudos Transversais , Diabetes Mellitus Tipo 2/complicações , Fadiga , Feminino , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/complicações , Obesidade/complicações , Sobrepeso/complicações , Inquéritos e Questionários , Sobreviventes/psicologia , Magreza/complicações
7.
Breast Cancer Res Treat ; 167(2): 537-545, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28965272

RESUMO

PURPOSE: Little is known about the importance of various factors which impair the quality of life (QOL) in survivors of breast cancer 1 year after diagnosis and over 1 year after diagnosis in China. Hence, the goal of this article is to quantitatively evaluate the factors which play an active role in impairing QOL 1 year after diagnosis and over 1 year after diagnosing survivors. METHODS: A population-based cross-sectional study was conducted at 34 Cancer Recovery Clubs across China from May 2014 to January 2015. The simplified Chinese version of the Quality of Life Questionnaire-Core 30 items (EORTC QLQ-C30) and the Breast Cancer-specific module QLQ-23 were used to measure QOL in 10794 Chinese women with breast cancer (1 year after diagnosis: 1029, over 1 year after diagnosis: 9765). Forward stepwise multivariable regression analysis was used to identify the most predictive factors for limitations on QOL. Partial R 2 values were calculated to appraise the independent proportion of explained variance within QOL by each factor included in the model. RESULTS: The participants had higher scores of role functioning, sexual function, sexual enjoyment, and financial difficulties. The uppermost predictors of functional status and QOL were financial difficulties and fatigue for the 1 year after diagnosis, respectively, and fatigue, financial difficulties, and systemic side effects for the long-term survivors. These symptoms explained approximately 28-53% of the variability within the function scores and QOL expect for sexual enjoyment and sexual functioning. Although sociodemographic and clinical factors had a relative importance to sexual function and sexual enjoyment, they were even smaller and had less of an impact on other dimensions. CONCLUSIONS: People who were more active and had an optimistic attitude towards life had relatively higher function scores. For the breast cancer patients 1 year after diagnosis, reducing the burden of fatigue might be a more preferable way to improve their functional status and QOL. Nevertheless, focusing on fatigue symptoms and systemic therapy side effects synchronously may present an especially worthwhile endeavor to enhance the long-term survivors' functional status and QOL.


Assuntos
Neoplasias da Mama/epidemiologia , Neoplasias da Mama/psicologia , Sobreviventes de Câncer/psicologia , Prognóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Mama/patologia , Neoplasias da Mama/fisiopatologia , China/epidemiologia , Fadiga/epidemiologia , Fadiga/patologia , Fadiga/psicologia , Feminino , Humanos , Pessoa de Meia-Idade , Otimismo/psicologia , Orgasmo/fisiologia , Qualidade de Vida , Inquéritos e Questionários
8.
Sci Rep ; 7(1): 11524, 2017 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-28912447

RESUMO

This study aimed to develop and validate an effective prognostic nomogram for advanced PDAC patients. We conducted a prospective multicenter cohort study involving 1,526 advanced PDAC patients from three participating hospitals in China between January 1, 2004 and December 31, 2013. Two thirds of the patients were randomly assigned to the training set (n = 1,017), and one third were assigned to the validation set (n = 509). Multivariate cox regression analysis was performed to identify significant prognostic factors for overall survival to develop the nomogram. Internal and external validation using C-index and calibration curve were conducted in the training set and validation set respectively. As results, seven independent prognostic factors were identified: age, tumor stage, tumor size, ALT (alanine aminotransferase), ALB (albumin), CA 19-9, HBV infection status, and these factors were entered into the nomogram. The proposed nomogram showed favorable discrimination and calibration both in the training set and validation set. The C-indexes of the training set and validation set were 0.720 and 0.696 respectively, which were both significantly higher than that of the staging system (C-index = 0.613, P < 0.001). In conclusion, the proposed nomogram may be served as an effective tool for prognostic evaluation of advanced PDAC.


Assuntos
Adenocarcinoma/patologia , Carcinoma Ductal Pancreático/patologia , Técnicas de Apoio para a Decisão , Nomogramas , Adulto , Idoso , Carcinoma Ductal Pancreático/mortalidade , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Análise de Sobrevida
9.
PLoS One ; 11(11): e0164971, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27812130

RESUMO

PURPOSE: The main goal of this study was to compare the quality of life (QOL) and its association with physical activity (PA) among patients diagnosed with different types of cancer. Based on the results, we tentatively present suggestions for the cancer health care model. METHOD: A cross-sectional study was conducted with 2915 cancer survivors recruited from multi-community cancer rehabilitation centers, all of which were affiliated with the Shanghai Cancer Rehabilitation Club. We collected data including socio-demographic characteristics and information about PA. All the subjects included were asked to complete the European Organization for Research and Treatment Quality of Life Questionnaires (EORTC QLQ-C30) and Functional Assessment of Cancer Therapy-General Questionnaire (FACT-G). Multiple linear regression models were employed to control the potential confounding factors. RESULTS: Lung cancer survivors reported the worst dyspnea. Colorectal cancer survivors claimed the highest level of constipation and diarrhea. Liver cancer survivors indicated greatest loss of appetite and financial difficulties. Generally, survivors with PA tended to reported better QOL, although these associations among liver cancer survivors were not statistically significant. Moreover, survivors of all cancer types who performed PA did not report significant lower level of constipation or diarrhea. The relationship between PA frequency and QOL among cancer survivors remained unexplored. CONCLUSIONS: Both QOL and its association with PA vary among survivors of different cancer types. The detailed results can assist clinicians and public health practitioners with improving health care management.


Assuntos
Exercício Físico , Neoplasias/fisiopatologia , Qualidade de Vida , Sobreviventes , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Saúde Pública , Inquéritos e Questionários
10.
Sci Rep ; 6: 32020, 2016 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-27558285

RESUMO

Immunotherapy is a novel treatment for advanced non-small cell lung cancer (NSCLC) patients. Immunotherapy includes two main broad classes of therapeutic vaccines and immune checkpoint inhibitors, as well as cytokines, biological response modifiers and cellular therapy. The present systematic review and meta-analysis aims to evaluate the efficacy and safety of different classes of immunotherapy in patients with advanced NSCLC. Literature search was done on Medline, Embase and Cochrane Library. The primary endpoints were overall survival (OS) and grade ≥3 adverse events. Twenty randomized controlled trials were finally identified in our study. Efficacy analysis indicated an improvement of OS in advanced NSCLC patients after treating by therapeutic vaccines and immune checkpoint inhibitors, but not for other immunomodulators. Safety analysis showed that immunotherapy was well-tolerated. All kinds of grade ≥3 adverse events were similar between experimental group and control group except that neutropenia and thrombocytopenia had a higher incidence in patients received vaccines. In conclusion, immunotherapy is a promising treatment for advanced NSCLC patients. Our findings will be further confirmed and supplemented by several phase II and phase III RCTs which are going to complete in near future.


Assuntos
Vacinas Anticâncer/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/terapia , Imunoterapia/métodos , Neoplasias Pulmonares/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Vacinas Anticâncer/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Humanos , Fatores Imunológicos/uso terapêutico , Imunoterapia/efeitos adversos , Neoplasias Pulmonares/mortalidade , Glicoproteínas de Membrana/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto
11.
PLoS One ; 11(6): e0157791, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27333326

RESUMO

OBJECTIVE: We aimed to investigate the associations between diabetes and quality of life (QOL) among breast cancer survivors. METHODS: A cross-sectional survey was conducted at 34 Cancer Recovery Clubs across China from May 2014 to January 2015. Quality of life was measured by the Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30) and the Quality of Life Questionnaire-Breast Cancer Module 23 (QLQ-BR23, simplified Chinese version). Information on social-demography, diagnosis and treatment of tumors, and diabetes mellitus were collected by self-reported questionnaires. Univariate analyses of covariance (ANCOVA) was performed to assess the difference in QOL between patients with or without diabetes mellitus, and multiple linear regression models were used to examine the associations after controlling for confounders. RESULTS: Diabetes, both of type 1 diabetes (T1DM) and type 2 diabetes (T2DM) significantly reduced QOL. This effect of diabetes on QOL is independent of tumor size, regional lymph node metastasis, distant metastasis and tumor stage index (TNM). After adjusting for different social-demography, diagnosis and treatment of the tumor, the tumor's stage and other chronic comorbidities, breast cancer survivors with diabetes got significantly lower scores in functional dimensions (including physical, role, emotional and social functionings measured by EORTC QLQ-C30; body image (BRBI) and future perspective (BRFU) measured by QLQ-BR23, as well as economic difficulties than those without diabetes (Padjusted<0.05). Diabetic patients also obtained higher scores in symptom dimensions, including fatigue, nausea and vomiting, pain, dyspnoea, insomnia, constipation and diarrhoea measured by EORTC QLQ-C30; side effects, breast symptoms and upset by hair loss measured by QLQ-BR23 (Padjusted<0.05). Compared to patients with T1DM, those with T2DM are likely to suffer more by loss of functioning. CONCLUSIONS: Diabetes was associated with the decreased QOL for breast cancer survivors.


Assuntos
Neoplasias da Mama/complicações , Neoplasias da Mama/psicologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Qualidade de Vida , Sobreviventes/psicologia , Adulto , Idoso , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/patologia , Feminino , Saúde Global , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias
12.
PLoS One ; 11(4): e0153047, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27073922

RESUMO

OBJECTIVE: To evaluate the accuracy of the McMonnies questionnaire (MQ) as a screening tool for dry eye (DE) among Chinese ophthalmic outpatients. METHODS: We recruited 27718 cases from 94 hospitals (research centers), randomly selected from 45 cities in 23 provinces from July to November in 2013. Only symptomatic outpatients were included and they were in a high risk of DE. Outpatients meeting the criteria filled out questionnaires and then underwent clinical examinations by qualified medical practitioners. We mainly evaluated sensitivity, specificity, diagnostic odds ratio (DOR), and area under the receiver-operating characteristic curve (AUC) to evaluate the accuracy of the questionnaire in the diagnosis of dry eye. RESULTS: Of all the subjects included in the study, sensitivity, specificity, and DOR were 0.77, 0.86 and 20.6, respectively. AUC was 0.865 with a 95% CI (0.861, 0.869). The prevalence of DE among the outpatients claiming "constantly" as the frequency of symptom was over 90%. Scratchiness was a more accurate diagnostic indication than dryness, soreness, grittiness or burning. Different cut points of McMonnies Index (MI) scores can be utilized to optimize the screening results. CONCLUSIONS: MQ can be an effective screening tool for dry eye. We can take full advantage of MI score during the screening process.


Assuntos
Síndromes do Olho Seco/diagnóstico , Inquéritos e Questionários , Adulto , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Pacientes Ambulatoriais , Sensibilidade e Especificidade , Adulto Jovem
13.
Appl Opt ; 53(27): G163-8, 2014 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-25322125

RESUMO

A speckleless illuminated modified-Gerchberg-Saxton-algorithm-type computer-generated hologram, which adopts a lower frequency of the iterative algorithm and calculation time, is proposed to code a hologram with two signals and position a multiplexing phase-only function, which can reconstruct the left and the right viewing holograms on the pupillary-distance position after the decryption and still maintain the content with high contrast and definition. The reconstructed image quality presents root mean square error of 0.03, with a diffraction efficiency of 87%, and signal-to-noise ratio of 8 dB after the analysis. Furthermore, two denoising techniques for the digital filter and optical suppression are combined, in which the speckle suppression with pseudorandom phase modulation and a rotating diffuser are utilized for successfully reducing the speckle contrast, which was reduced to below 4%. The goal was to reduce visual fatigue for the viewers.

14.
Opt Express ; 21(18): 21264-72, 2013 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-24104000

RESUMO

A micro-prism film, with spectral characteristics, is attached on a display panel to show images appearing with + 10° ~ + 50° and -10° ~-50° bright regions and with a + 10° ~-10° dark region. When both eyes separately receive the bright region and the dark region of an image, interocular delay would appear to generate a stereo perception. With the optical simulation software, LightTools 7.3.0, to simulate the brightness change, the light with lower brightness appears on the 0° region and the light with the highest brightness appears on the ± 10° region. The optimal viewing distance of 25 cm could accurately deliver the image with shading parallax to both eyes. The actual measurement of brightness presents the shading distribution, achieving the condition of binocular retinal illumination, and the angle of visibility appears on the ± 50° region, causing interocular delay so that the viewer generates the stereo perception.

15.
Opt Express ; 21(7): 8474-82, 2013 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-23571937

RESUMO

Different from traditional panorama stereo acquisition technique shooting with numerous cameras, this study equips a double-symmetric prism in front of a single-lens camera to acquire images from four different angles of view, and the images acquired from the cameras every 20 degrees complete a pair of panorama stereo images with vertical angle of view ( ± 16 degrees) by image-based rendering. The panorama stereo acquisition technique reduces the number of cameras by three-fourth, and the acquired images contain vertical angles of view. Moreover, the image resolution is enhanced several times of the resolution of integral photography without moiré effect.


Assuntos
Aumento da Imagem/instrumentação , Lentes , Fotogrametria/instrumentação , Refratometria/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento
16.
Opt Express ; 21(25): 31062-71, 2013 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-24514680

RESUMO

We propose a system that reduces laser display speckles by vibrating the light pipe. A small displacement of the light pipe appears to allow the total reflection of the laser, thereby resulting in a homogenized speckle field that changes with time. In this case, the speckle interference generated by the pattern projected by the laser through the light pipe destroys the spatial homogenization of the laser beams when the light pipe is vibrated. Moreover, when the light pipe begins the sequential vibration, the phases and paths of the beams are changed after the beams traverse the light pipe. Consequently, temporal speckle wavefront superposition can homogenize the luminous intensity distribution of the speckle pattern. This process reduces the speckle contrast to less than 4% while maintaining a luminous intensity of greater than 70%.

17.
Appl Opt ; 51(7): 877-82, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22410889

RESUMO

The diffractive optical element blazed grating is proposed as the beam splitter for autostereoscopic displays in this study. With Lithographie Galvanoformung Abformung and inductively coupled plasma reactive-ion etching, a four-level blazed grating structure is produced. Moreover, highly translucent polydimethylsiloxane is transformed into symmetrical four-level blazed grating films. The experimental results show that the film can successfully transmit the left and the right images to the accurate positions, and the diffraction efficiency is 70.4% and the contrast ratio is above 80%, presenting the original stereoscopic image without it being affected by brightness and crosstalk. In the experiment of stereoscopic imaging, both the left and the right images could be clearly acquired, which proves the feasibility of blazed gratings as practical for the beam splitter of autostereoscopic displays.

18.
Opt Lett ; 36(17): 3422-4, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-21886231

RESUMO

This study proposes a diffractive autostereoscopic display technology that utilizes blazed grating embedded in the liquid crystal panel to deliver a stereo image pair to both eyes. Having the diffractive red green blue beams as the color source of the panel, color filters are no longer required in this system. From the simulation analyses, not only could the brightness achieve 77.90%, but no serious chromatic aberration or cross talk appeared.


Assuntos
Imageamento Tridimensional/instrumentação , Cor , Desenho de Equipamento , Luz , Fenômenos Ópticos , Fatores de Tempo
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