Elasticsearch映射-Asciifolding过滤器

Question

我有一个映射：

{
    "settings": {
        "index": {
            "refresh_interval": "-1",
            "number_of_shards": "4",
            "number_of_replicas": "1",
            "analysis": {
                "analyzer": {
                    "lower_ascii": {
                        "filter": [
                            "lowercase",
                            "asciifolding"
                        ],
                        "type": "custom",
                        "tokenizer": "standard"
                    }
                }
            }
        }
    },
    "mappings": {
        "doc": {
            "dynamic": "strict",
            "properties": {
                "field_name": {
                    "type": "text",
                    "analyzer": "lower_ascii",
                    "fielddata": true
                }
            }
        }
    }
}

在映射中设置了asiifolding和小写过滤器。但是该字段的值既不是ascii也不是小写？像“NámestieLudvíkaSvobodu”这样的原始字符串...我是否缺少某些东西或不正确？感谢您的帮助。